Chapter XI.
PRACTICAL AQUARIUM SETUP AND MAINTENANCE
My goal in writing this book was to explain ecological principles (allelopathy, biofilms, sediment chemistry, etc) behind keeping attractive, low-maintenance planted tanks. (For want of a better term, I call them ‘Low-tech’ aquariums.)
Maintaining any aquarium is difficult. Pitfalls abound. There are just too many variables in aquarium keeping for one single book to address every possible pitfall. So I caution beginning hobbyists that there are no guarantees that even if they diligently follow the methods I use that they will be pleased with the results.
The well-established home aquarium is a complex ecosystem. Even when one tank is set up identically to another, it will surely– over time– take on ‘a life of its own’. You cannot purchase an ecosystem. All you can do it set it up the aquarium as best you can and hope that it will develop in a way that pleases you.
A.Typical Pathways for Beginning Hobbyists
Countless beginners set up their first tank with great enthusiasm. The plants, fresh from plant nurseries, are lush and algae-free. The fish, chosen carefully, are healthy and active. The water is crystal clear, sparkling, and bubbling. The gravel, having been thoroughly washed, is ‘clean as a whistle’. The tank looks exactly like the display tanks in aquarium stores and magazine photos.
It is not long, though, before this pretty picture turns sour. The plants do not grow well or start dying, and algae begins to grow everywhere. Unless the owner changes the water and vacuums the gravel frequently, the fish start to sicken. Beginning hobbyists are instructed to use algaecides, do more water changes, do more gravel cleaning, buy bigger filters, and feed their fish less. Hobbyists may try to cultivate plants again, but this time they add fertilizers. “Maybe fertilizer will keep the plants alive.”) Unfortunately, fertilizers usually do not help; the algae only grows better, and the plants grow worse.
At this point, many beginners understandably give up on plants altogether. (“After all, plants are not that important anyway.”) And so, in defeat, they switch to plastic plants. To keep their fish healthy, they laboriously continue to change the water, clean the filters, and vacuum the gravel. Not much fun… Such discouragement, especially with keeping plants, is common within the aquarium hobby. But it should not be that way.
A few energetic beginners, not so easily defeated, decide to take the plunge and set up ‘High-tech’ tanks. These aquariums are generally successful and quite beautiful. The problem is that High-tech aquariums require a tremendous commitment in time and money.
B.Setting up a Basic, ‘Low-Tech’ Aquarium
I set up my first true planted aquarium in 1988. It was different than all those I had set up beforehand. I had always kept fish successfully, but plants were another matter. I had tried many times to grow plants in my fish aquariums and had consistently failed; the plants didn’t grow and the tanks were taken over by algae. This time, I ignored all the many warnings from the hobbyist literature not to use sun and soil. (After all, plants and fish in natural habitats were doing well enough with sun and murky sediments?)
I placed the tank next to a large window with a Southern exposure so that the sun shone through the back of the tank for a few hours on most days. The 29 gal I used was a nice size (12” wide X 30” long X 18” high)– high enough that taller plants could reach their full height. The artificial light was only a single 20-watt fluorescent bulb. I layered the tank bottom with 1½” of ordinary potting soil and covered the soil layer with a 1½” layer of small, natural gravel.
At the time, I had no idea which plants would grow well in this untested setup. Therefore, I bought a wide assortment of plants– various species of swordplants, Vallisneria, Bacopa, Ludwigia, Cryptocoryne, Aponogeton, Sagittaria, etc. Many species I was unfamiliar with and some plants were not in very good condition, but I used them anyway.
I chose fish that would stay small and would not dig– neon tetras, guppies, mollies, platies, dwarf gouramis, and a male Betta. The fish seemed right at home.
Within a week the response of the plants was phenomenal. I had never seen plants in an aquarium grow like this. Plants that had been so weak and unhealthy at planting that I thought would die, slowly recovered and began to grow. The Amazon sword quickly got so big that I had to remove it. Over the years, the Crypts took over the tank and many of the other plant species gradually disappeared. Now the tank contains a massive grove of tall, red Crypts, some of the feathery stem plant Ambulia, and a little duckweed. It is still an attractive, easy-to-keep tank.
Since the success of that first tank, other hobbyists have set up similar tanks with ordinary soil, lots of plants, and a little sunlight. They have been thrilled with the results.
C.Major Factors
1.Fish
I choose fish that will fit the tank and avoid fish that get too large as adults for their tank. (It is distressingly hard to find a home for a huge pet Oscar or a Plecostomas.) For small tanks of 10 or 20 gal, dwarf gouramis, small tetras, dwarf cichlids, White Clouds, and Zebra danios are nice. Angelfish, the larger gouramis, Congo tetras, and Rainbowfish fit well in larger tanks of 50 gal or more. All these fish are easily kept with plants.
Finding healthy fish requires effort and/or luck. Sadly, about half of the fish I have purchased from some aquarium stores have died or brought disease into my tanks. Many beginning hobbyists report dismal results with newly purchased fish. Too often beginning hobbyists blame themselves for something they did or did not do, when it may well be that the fish were diseased to begin with. Most stores do not screen incoming fish for disease or sterilize tanks inbetween shipments. With fish shipments from multiple sources, the potential for disease transmission is enormous.
Q. How do you catch fish in a heavily planted tank?
A. I keep bricks and/or rocks at one end of my aquariums in order to easily catch the fish (see Color Plate 1). I herd the fish to the rock end of the tank and quickly insert a tank-divider between the fish and the rest of the tank. After removing the rocks, I can easily catch the fish without disturbing the rest of the aquarium.
Ferns can soften the effect of the rocks and increase total plant growth in the tank. I especially like to use lava rocks covered with Java fern. Getting the ferns to grow on the rocks is easy. I just secure their rhizome to the rock with string. The ferns will eventually attach and cover the rock.
Because of the disease risk, it is worth seeking out fish vendors that buy healthy stock and employ measures to control disease spread. Also, I have had few problems from fish purchased directly from the breeder.
Adding new fish to an established tank is always risky. Often the new fish, no matter how healthy they appear, can introduce disease into the tank. Mycobacteriosis (“Fish TB”) is a very common disease that may take several weeks or months to manifest itself. I’d rather just enjoy the fish I have or breed new ones. The other alternative is to set up a quarantine tank for newly purchased fish. Recommended quarantine time is at least 2 weeks, but the longer the better. Hobbyists that compulsively buy fish and put them directly into their large, established tanks sometimes end up with no fish.
Finally, euthanizing fish is an unfortunate reality of aquarium keeping. Fish can get incurable diseases and tumors. Prolific fish, especially livebearers, will multiply to the point where they cannot be sold or given away. I dispose of excess fry and moribund fish with a quick dip in carbonated water. (They are never flushed down the toilet to a cruel, lingering death in a sewer line or septic tank.)
Many aquarium stores carry a dizzying assortment of medications, some effective and many not. Beginning hobbyists are lulled into assuming that fish diseases can be easily cured. That has not been my experience.
UV sterilizing filters can be highly effecting in preventing disease problems. UV (ultraviolet) light kills bacteria suspended in the water. It doesn’t kill filter or soil bacteria, because they are attached. Nevertheless, a UV sterilizing filter greatly reduces the number of unfamiliar (immunologically speaking) and potentially pathogenic bacteria that fish are exposed to. It gives a newly purchased, and often stressed, fish precious time to develop antibodies and natural immunity. I was able to control a deadly mycobacteriosis outbreak in my Rainbowfish with UV sterilizing filters.
Experts can help. When my guppies were dying inexplicably, I sought help from a fish veterinarian at the local vet school. I learned that my guppies had fish nematodes (Camallanus). I cured the fish by feeding them the prescribed “dewormer”.
Recently (2009), I started keeping Red Cherry Shrimp and Grass Shrimp. These small invertebrates can be kept in small planted tanks without a filter or heater and will eat almost anything. They are easier to maintain than fish, provided they are protected from heavy metals in fresh tapwater (see pages 25-26). [Invertebrates are particularly sensitive to heavy metals.]
2.Light
Providing adequate lighting for the planted aquarium can easily degenerate into a confusing muddle of technical terms about light intensity and wavelengths. Beginning hobbyists should realize that many lighting systems will work. The only ones I would avoid are those designed for marine tanks that often have far more light intensity and blue light than what is required for a planted tank. One must not forget that aquarium plants are basically shade plants; they need much less light than many terrestrial plants, floating plants, emergent plants, and marine corals. For example, one submerged plant (Myriophyllum brasiliense) can only use about 10% of the light intensity of its emergent form (see page 146). Excess light only stimulates algae. Here is what I use for my tanks:
1.One to three watts of fluorescent light per gal of tank water. I use either ordinary (T-12) fluorescent lights or CFL (compact fluorescent lights).
2.For bowls and small tanks (1-10 gal), I use desks lamps or clamp lights equipped with CFLs (Fig XI-1). Clamp lights can be purchased at many hardware stores.
Figure XI-1. Clamp Light (10.5” diameter) with 13 watt Screw-in CFL. The clamp light, which can be purchased at some hardware stores, comes with a clamp and an electrical cord (not shown in photo).
3.For bigger tanks, I use dual strip-lights. For example, I use two 55 watt CFLs over one 55 gal tank and two 40 watt T-12s lights (one Cool-white and one fluorescent light designed for growing plants) over another 55 gal tank.
4.I use glass lids for all my tanks. They are simply glass rectangles prepared by local glass cutters from ordinary 1/8” thick glass. I ask the glass cutters to notch off a 2” triangular piece from the larger rectangles (the notch provides an exit for aquarium tubing and power cords). After purchase, I sandpaper the sharp edges. The smaller rectangle (~3.5” wide), to which I later glue on a handle, goes at the front of the tank. The larger rectangle (~7-8” wide), usually with a notch, goes at the back. No hinge required. A 55 gal tank, with its center brace, requires 4 rectangles (two wide and two narrow). A two gal tank gets one rectangle. The 50 gal, which doesn’t have a center brace, requires three long rectangles of slightly thicker (3/16”) glass.
5.Some fluorescent lights come with color temperature (Kelvin) ratings. For them, I choose any light with a color temperature between 5,000K and 7,000K.
6.Avoid buying tall tanks (> 18 inches high) unless they will be getting window light (light intensity is quickly reduced as it passes through water).
7.I use light timers to automatically schedule a 5-4-5 Siesta Regimen. Lights are on for 5 hr in the morning (7 AM to noon), turned off for 4 hr (between noon and 4 PM), and turned on again for 5 hr (4 PM to 9 PM). Tanks with emergent plants get 14 hr continuous light.
8.Expect to replace ordinary (T-12) lights every year. CFLs will last much longer.
9.Take full advantage of available window light.
Aquarium plants need a daylength of at least 12 hr to do well. For example, one plant (Hydrilla) grew three times faster when the daylength was increased from 10 hr to 12 hr [1].
Short daylength (less than 12 hr) may signal plants, hormonally speaking, to stop growing. Many plants perceive short daylength as a prelude to winter and/or a dry season. Their growth rate slows or may stop altogether. Daylength is a powerful environmental cue for aquatic plants. That is why I recommend a daylength of at least 12 hr (I use 14 hr).
That said, keeping the overhead lights on for 12 hr (or more) creates another set of problems—increased electricity consumption, potential algae problems, and during the summer, more tank overheating. The Siesta Regimen, which provides plants with an afternoon nap, nicely addresses these problems. A midafternoon siesta mimics the natural condition—a temporary overhead clouding during a summer afternoon.
Moreover, a siesta allows CO2 regeneration. With continuous light, plant photosynthesis depletes most of the CO2 by late morning (Fig. XI-2). This means that during the afternoon, plants are competing for an ever dwindling supply of CO2. Algae, which is more adept than plants in taking up CO2, gains an afternoon advantage over plants.
Figure XI-2. Effect of Afternoon Siesta on CO2.
I measured CO2 levels in a tank (using a LaMotte test kit and the titrimetric method for free CO2) on 2 separate days.
One day, the tank got continuous light from 7 AM (starting Time Point on graph) to 9 PM (the ‘14 hr’ Time Point). I made my last CO2 measurement at 8 PM, one hr before I turned off the tank lights.
The next day, I monitored the tank again, except that I gave it a 4 hr afternoon siesta (turned off overhead lights from noon to 4 PM).
I obtained a similar pattern with other tanks.
With the Siesta Regimen, though, CO2 is regenerated when the lights are off. Indeed, Fig XI-2 shows that CO2 rebounds almost to pre-dawn levels. My explanation for the rapid CO2 rebound is that rampant plant photosynthesis precedes the 4 hr siesta. Morning photosynthesis oxygenates the water, and in turn, stimulates bacterial metabolism. Bacteria quickly (within minutes) respond favorably to oxygenation. Nothing else explains such rapid CO2 regeneration.
The Siesta Regimen gives plants the long daylength they need and saves electricity. It provides light when plants have enough CO2 so that they can actually use the light. Finally, it reduces algae’s “afternoon advantage” over plants.
Fluorescent light is generally satisfactory for growing plants in aquariums.
One investigative hobbyist [2] used the experimental method to determine the best fluorescent lights for growing 5 species of freshwater plants and marine macroalgae. The starting hypothesis was that Vita-Lite™, a full-spectrum fluorescent bulb, was better than other fluorescent lights. However, the experiment proved otherwise.
For example, Elodea produced the most oxygen (>45 ml) when exposed to a combination of Cool-white and Vita-Lite (Fig. XI-3). Pure Cool-white gave the next best results (>35 ml) and out-perfomed pure Vita-Lite (25 ml). Results for the other plants and algae were similar to those for Elodea, with all organisms producing the most photosynthetic oxygen with Cool-white combined with Vita-Lite. Again, second best for all was not pure Vita-Lite but pure Cool-white.
Figure XI-3. Effect of Fluorescent Lighting on Elodea Photosynthesis.
Elodea was placed in sealed testtubes. ‘Oxygen Produced’ is the water volume displaced by the photosynthetic oxygen produced after 24 hours of continuous light from two 40 watt fluorescent lights.
{Figure from Richards [2] redrawn and used with permission of Freshwater and Marine Aquarium.}
The fact that plants did very well with Cool-white, which produces mostly green-yellow light was unexpected. One would have expected the plants to do better with Vita-Lite, because Vita-Lite was designed for growing plants. Its spectrum, which is rich in red and blue light, better matches the light absorption of plant chlorophyll than Cool-white.
Cool-white was found to gives off 13% more photosynthetic light than Vita-Lite [3]. Perhaps Cool-white’s slightly higher light intensity explains its better performance? However, I would also argue that green-yellow light is what many submerged aquatic plants encounter in their natural environment. Aquatic light is not like terrestrial light where the blue and red wavelengths predominate (Fig. XI-4). Aquatic light is unique. This is because the water itself (H2O) absorbs red light, while DOC absorbs blue light. What is leftover for plant photosynthesis is mainly green-yellow light. Aquatic plants may have adapted their photosynthetic machinery (over the course of evolution) to use green-yellow light fairly efficiently. Thus, the assumption that aquatic plants grow best with full-spectrum light may not be valid.
Figure XI-4. Aquatic Light versus Terrestrial Light.
Spectra are from actual measurements [4]. ‘Terrestrial Light’ includes direct sunlight (no clouds) and diffuse light (light on an overcast day).
‘Aquatic Light’ was taken at a 1 meter (~ 3 ft) depth at 3 lakes in Scotland. Light intensity (µmol/m2/s) was about 2,000 for direct light, 500 for diffuse light, 1,200 for Loch Borralie, 700 for Black Loch, and 300 for Loch Leven.
[Figures modified slightly and used with permission from the Annual Review of Plant Physiology, Volume 33, © 1982, by Annual Reviews, www.annualreviews.org]
3.Plant Selection
Finding plants that will grow well is essential to having a natural, low-maintenance tank. Only healthy, growing plants can purify the water, protect the fish, and control algae.
Consulting other hobbyists may be helpful, but some advice on plant selection is based on generalities and misconceptions as to what constitutes good growth. For example, Amazon swordplants are sometimes mistakenly combined with Angelfish in acidic, softwater tanks, but swordplants do much better in hardwater.
One approach to finding plants that will do well in an aquarium is just to plant as many species as possible and let the plants sort it out. This is what I do. I probably have planted over 50 different species at one time or the other. I found that I could always count on the Amazon Swordplant (Echinodorus bleheri), E. major, E. tenellus, Echinodorus ‘Ozelot’, Sagittaria subulata, and S. graminae for fast, quick growth. Anubias nana, Cryptocoryne wendtii, C. balansaea, and Java Fern take longer to establish, but once established, they grow well. Best floating plants for me have been Water Sprite (Ceratopteris thalictroides) and Frog Bit (Limnobium laevigatum). Stem plants Bacopa monnieri and Rotala rotundifolia have always done well for me; other stem plants not so well. I obtain plants from stores, mail-order suppliers, and other hobbyists.
Beginners should be aware that many plants currently popular with High-tech hobbyists demand more CO2 than a Low-tech tank can provide. I would put popular “carpet plants” in this category. High-tech hobbyists usually maintain CO2 at 13 to 25 mg/liter via CO2 injection. The CO2 in my tanks fluctuates during the day between about 1 and 10 mg/l. That may not enough for some species when they are competing with more robust plants.
Still, there are many plant species that do very well in Low-tech tanks. In the final analysis, the beginning hobbyist should start out with as many species as possible and find the ones that work best. Here is where I would focus my time, money, and energy.
The first 2-3 weeks are critical. If enough robust plants get established during the first few weeks, they can easily ward off algae. However, if there aren’t enough plants or they are poor growers or growing conditions are sub-optimal, algae can make tank life very difficult for plants. Once algae becomes entrenched, it can block plant growth by removing all CO2. Plants can’t photosynthesize and oxygenate their roots, so they start to die, decompose, and add to the problem. Tank startup can go quickly downhill.
For hobbyists who are not in a hurry, the DSM or Dry Start Method [6] is a clever way to get plants established. You set up the tank but then wait several weeks before adding water and submerging the plants. Most aquarium plants are sold in their emergent form, so their adaptation to the tank is easier than if they are immediately submerged. Moreover, aquatic plants grow much faster in air than water (see Ch IX ‘The Aerial Advantage’), so they get their root systems established faster. Using the DSM and waiting 10 weeks, I was able to get some previously impossible plants [Hemianthus callitrichoides and Eleocharis acicularis (Dwarf Hairgrass)] to form lush, dense carpets (see Color Plate 4).
D.Guidelines in Aquarium Keeping
Tanks– Small 1 gal bowls and 2-10 gal tanks are perfect for first-time hobbyists for finding adaptive plant species and learning how to work with soil. Excess plants from a small tank can be later used to start larger tanks.
Tank Stands- I place a cushioning piece of wood or pressed fiber-board between the stand and the tank bottom, especially for larger tanks (>20 gal). The board insulates the tank bottom from cold air and prevents point stresses that can cause the tank to leak later on.
Adequate Lighting and Glass Lids (see pages 178-181).
Substrate- For growing plants, the tank bottom should be layered with 1” of unfertilized soil covered with no more than 1” of gravel. If the gravel or soil layer is too deep, the soil could become severely anaerobic and kill the plants. I have gotten good results with ‘organic’ potting mixes. They have a low NPK, do not contain chemical fertilizers, and are well-composted. For growing plants confined to pots where the soil can easily go anaerobic, I use a mineral soil rather than an organic soil. See pages 137-140 for other factors.
Gravel- The gravel used to cover the soil should be fairly small (2-4 mm). Sand works okay, but I would not make the sand layer deeper than about 0.5-0.75 inch. Sand tends to form a tighter seal than gravel and can “suffocate” the soil layer. Stones or pebbles should never be used. Not only are the pebbles inhospitable for plant roots, they can endanger the fish. (Uneaten fishfood trapped between the pebbles can rot anaerobically and pollute the tank, possibly killing the fish.)
Plants- see pages 181-182.
Fish feeding- Despite warnings in the hobbyist literature, I always feed my fish well plus a little extra for the plants (see 2nd Q&A on page 80). True overfeeding is evidenced by cloudy, smelly water or fishfood rotting on the tank bottom. (In my tanks, there are never any traces of leftover food or water cloudiness.)
Fishfoods- I buy dried foods in larger quantities, store most in the freezer, and keep a small amount out for everyday feeding. I like to give my fish special treats once a week. ‘Treats’ include raw chicken liver, boiled egg yolk, and frozen Brine Shrimp. The treats are all stored in the freezer. I chop them up before feeding. Most of the time, though, I just feed the fish flakefood, pellets, and freeze-dried bloodworms.
For successfully raising baby fish, a Low-tech tank is ideal. The soil layer provides an ideal home for numerous protozoa that baby fish can eat. Indeed, I have often raised a small number of Betta fry without feeding them anything for the first month.
When the fry reach baby guppy size, I usually feed them live baby brine shrimp. Most fish breeders advocate hatching daily batches of fresh brine shrimp eggs in clean saltwater. This requires wasting expensive eggs and the continuous preparation of saltwater. Instead, I feed the brine shrimp so that the culture lasts about a week. To a quart of saltwater, I add ¼ teaspoon of brine shrimp eggs and just a pinch of powdered food (fry food, Baker’s yeast, etc). I aerate the water vigorously via an air-stone. Bacteria start to multiply (the water should be clear or just slightly cloudy). Each day, I remove just enough shrimp to feed the baby fish (if you continuously add too many shrimp to the rearing tank, it will become infested with the nuisance invertebrate hydra). I reuse the salt water (after straining out the old egg shells) for at least a month. The main impediment to getting good hatches is not bad eggs but metal toxicity (the hatching of brine shrimp eggs was found to be exquisitely sensitive to heavy metals [5]). Therefore, I always add a water conditioner that neutralizes heavy metals to my saltwater preparations.
Medications and chemicals- I avoid salts, antibiotics, copper, dyes, etc, which often harm the tank’s ecosystem without curing the original problem.
Moderate fish load- Tanks with a moderate fish load are easier to take care of and less vulnerable to unforeseen problems (malfunctioning filters, power outages, etc).
Water changes- Frequent water changes should be unnecessary in well-established tanks. I change about 25 to 50% of the water every 3-6 months. New setups may require frequent water changes, because a freshly submerged soil releases considerable nutrients (see page 131).
Gravel cleaning- Gravel cleaning is detrimental in planted aquariums, because it prevents nutrient replenishment of the substrate.
Filters and water movement- Tanks with a soil layer and healthy plants will remove ammonia naturally, so bio-filters are unnecessary and possibly counter-productive (see pages 111-112). However, for large deep tanks, filters do help by distributing heat and keeping the water oxygenated.
For my 50 and 55 gal tanks, I use inexpensive submerged filters. They are easier to use than canister filters and less prone to power-outage problems (see page 73). The AquaClear powerhead with a ‘Quick Filter’ attachment is a good mechanical filter. It comes in handy to remove soil turbidity after moving plants around. Submerged filters come with suction cups that attach to the inside glass, thereby making it easy to move the filters. Sometimes I lower the water line a few inches and move the filters down to provide space for emergent plant growth.
Charcoal filtration– Routine use may be detrimental, because it removes DOC (dissolved organic carbon) that provides CO2 for plants (see page 59). However, fresh charcoal can quickly remove any dangerous organic chemicals (e.g., herbicides, etc). It will also remove any excessive yellow/brown coloration in the water due to tannins. (Tannins absorb light and could possibly limit plant growth.)
Airstones- Airstones should be used if the fish are showing distress or gasping at the water surface. In new tanks, a highly organic substrate (e.g., fresh potting soil) may pull oxygen out of the water. If the fish are doing fine, however, airstones should be used sparingly or not at all. For airstones quickly remove CO2-- the one nutrient that aquarium plants need more than any other nutrient (see page 88). I sometimes use vigorous aeration for tanks with emergent and floating plants (CO2 degassing will not inhibit them, because these plants get their CO2 from the air not the water.)
Pruning, thinning and transplanting- I remove excess plant growth to allow for fresh growth and the ongoing uptake of water nutrients. I snip off the outer, older leaves of larger Swordplants. I pinch off the leaves of Cryptocoryne. I try not to cut the aerial growth of emergent plants. Because floating plants are such good water purifiers, I don’t begrudge thinning them out. Excessive pruning can cause algae problems.
pH- If the aquarium is balanced, the pH should not become acidic over time (see page 4). Some muncipal tapwaters may have an artificially high pH (above 8) to protect metal pipes from acid corrosion. In this situation, it may help to bring the pH down before adding water to the tank. I do not recommend, though, that hobbyists try to maintain a target pH by adding chemicals to the tank water. All my tanks have an alkaline pH of 7-8. It’s less than perfect for plants, but I have learned to accept it.
Plant fertilization- Artificial fertilization with CO2, trace elements, and macronutrients is unnecessary if the tank contains a fertile substrate, the fish are fed well, and nutrients are not removed by over-zealous tank cleaning.
Water hardness- Water should not be too soft. Softwater is depleted of several important major nutrients. Plants may do poorly or even die (see page 114). Table XI-1 categorizes water hardness. Hobbyists with excessively softwater (GH less than 4) and poor plant growth may need to increase water hardness (see pages 86-87).
Table XI-1. Water Hardness Categories
| Classification | ppm or mg/l CaCO3 | GH or °dH |
| Very Soft | 0-70 ppm | 0-4 |
| Soft/Hard | 71-140 | 5-8 |
| Medium Hard | 141-320 | 9-18 |
| Very hard | >321 | >18 |
Note: Water hardness (combined Ca and Mg concentrations) is reported by water treatment plants as ppm CaCO3. Hobbyist test kits, however, usually quantify water hardness as GH, German degrees of water hardness. (One GH = 17.8 CaCO3)
Chloramine- Municipal water may contain chlorine or chloramines. Fish can tolerate traces of chlorine; excessive chlorine can be removed by degassing. Chloramines need to be removed by using specific water conditioners.
Snails- Although snails are frequently disparaged by aquarium hobbyists, they do not eat plants and are actually quite useful. Snails clean plant leaves of debris, algae, and bacteria. They speed decomposition, so that nutrients recycle more quickly to plants. Malaysian Trumpet snails tunnel into the substrate, thereby aerating the substrate. Many fish (Clown loaches, Bettas, etc) relish snails (these fish can be used to control excessive snail populations.) I keep snails in all my aquariums.
Temperature- I have given up on trying to keep my tanks at a constant and supposedly ideal 78°F. (The temperature in my tanks varies from 72-85°F degrees depending on the season, heater, etc.) During summer, I turn the heaters off and open up the top covers to allow the hot air trapped under the lights to escape. (On especially hot days, I keep a fan on nearby.) The fish and plants in my tanks seem to have adapted.
REFERENCES
1.Spencer DF and Anderson LWJ. 1986. Photoperiod responses in monoecious and dioecious Hydrilla verticillata. Weed Science 34: 551-557.
2.Richards K. 1987. The effects of different spectrum fluorescent bulbs on the photosynthesis of aquatic plants. Freshwater and Marine Aquarium (July issue), pp. 16-20.
3.Mohan P. 1998. Converting foot-candles or Lux to PAR: Values for some common fluorescent lamps, and what to do with them. The Aquatic Gardener 11(6): 182-190.
4.Smith H. 1982. Light quality, photoperception, and plant strategy. Ann. Rev. Plant Physiol. 33: 481-518.
5.MacRae TH and Pandey AS. 1991. Effects of metals on early life stages of the brine shrimp, Artemia: a developmental assay. Arch Environ Contam Toxicol 20: 247-252.
6.Barr T. Dec 2009. Dry-Start Method. Freshwater and Marine Aquarium, pp 54-61.