|bkh99 ||01-03-2010 01:02 AM |
Starting a Planted Tank Part One
After being out of the hobby for about 8 years I decided to set up aquariums once again, and this time I decided to go for the live planted tank. I thought I might share a few of my experiences gained. I did not want a massive power bill, and so I decided on ‘low light tanks'. I changed the light bulbs around the place over to those new 15 watt screw in florescents and I also stopped putting the computer on standby when not in use, and the result of making these simple changes was that I could run three aquariums while my power bill only increased by about ten dollars a month. I was very confused by a lot of conflicting information available on the internet, and so finally I had to rely upon my own judgment, and consequently had to learn by experience by making my own mistakes. For my 55 gallon long tank, I set inexpensive potting soil, with no additives, out in pails of water on the balcony to bake in the sun, which was supposed to help the soil rid itself of the organics that produce hydrogen sulphide (sewer) gas in a planted aquarium. I was intending to mimic nature, by duplicating the conditions aquatic plants encounter in the wild (this would mean creating a layer of sandy silty loam covered with a top layer of sand or gravel). To achieve this effect I mixed the potting soil with mineral rich black onyx sand (Seachem branded) as well as some iron rich Laterite. I laid this out about two to two and half inches thick on the bottom of the aquarium and then covered with about two inches of fractated baked clay chips (these are flat tiny chips of baked clay that overlap and seal in the soil, while at the same time being very gentle on bottom feeders- no sharp edges, etc). I then planted the tank with ‘low light plants' and then found that the tank was burping and expelling hydrogen sulphide gas for almost six months, and so it was not possible to add any fish (the tank literally smelled like ‘manure', to use the polite term). On my twenty gallon (tall) I used a thinner layer of this soil mixture (about one inch) topped with a layer of ‘Eco-Complete' nutrient rich plant gravel. This tank never produced any hydrogen sulphide gas, as oxygen was able to penetrate down to the soil level due to the shallow depth of the substrate, and the bacteria that produce this gas are anaerobic (they only survive in an environment devoid of oxygen). Fortunately ‘low light' plants are also ‘marsh adapted' and so the plants on my fifty five gallon long were able to survive the toxic conditions and eventually sent roots down to the top soil in the bottom of the tank, and since plant roots release oxygen, this removed the bacteria producing the hydrogen sulphide gas. On my ten gallon tank I took a different approach. I baked ordinary potting soil in the oven so as to kill all the naturally occurring bacteria. I then placed a thick layer of this potting soil on the bottom of the gallon tank (three and a half inches). I mixed into the soil a generous amount of Seachem Stability, which consists of spores of specially selected bacterial strains that do not produce hydrogen sulphide gas. I then sealed in the soil by covering it with a layer of sand (the type commonly used in marine aquariums, which has a slightly larger grain size). This tank has never produced hydrogen sulphide gas and the Seachem product does do what it claims to do. This baking the soil approach would have saved me six months of dreadful conditions in the 55 gallon long, and I could have also avoided leaching nutrients out of the soil before placing it into the tank (the common advice you get is to leach your soil of nutrients, then put it into the tank, advice that I found nonsensical, because plants need nutrients and that is the point of mimicking nature by creating a rich silty loam covered with sand). The plants in the ten gallon tank require constant pruning and are growing very aggressively (I can't leave them for over a week without pruning or they begin to block the light). At the moment I have never had to fertilize these plants, and they are doing just fine so far with just the original potting soil combined with fish waste products. I can never ‘vacuum' any of these tanks, because of the plants, and so therefore I have included Malaysian trumpet snails, which are a type of snail that burrows down into the substrate and are like little plows that constantly turn over the surface at the tank bottom, working fish waste down into the soil, and keeping the tanks spotless, while at the same time assisting in fertilizing the plants. On the ten gallon tank I use one single 15 watt T8 bulb, which is more than adequate (seeing is believing, as the aggressive healthy plant growth in that tank indicates). I also use a pop bottle set up and one of those C02 step ladder things (where the bubbles roll back and forth up a set of ramps, shrinking in size and dissolving into the water as they climb) in order to inject extra Co2 into both the ten and twenty gallon tanks. Plants are about 50 percent carbon, and the aggressive plant growth I get in both tanks indicates that this step ladder approach to C02 injection works fine on small tanks. One thing I do not like about those step ladders is that for some reason, from time to time, the bubbles only roll part way up the ramp, and then for some reason they park on one spot, until enough bubbles build up and then suddenly one giant bubble will shoot up the ramp. However despite all these strange behaviors, the plants are always doing very well. One the twenty gallon tall I have included one of those store bought C02 yeast fermentation bottles and I hang the bottle inside the aquarium, hiding it behind the plants. I also do this on the fifty five gallon long. Yeast production is temperature dependant, and I have found that I can maintain a consistent predictable rate of bubble production by keeping the yeast mixture at the constant temperature of the aquarium. I use one half cup of sugar, two teaspoons of baking soda (as an acid buffer, to extend the life of the yeast mixture) and then just a few grains of ordinary bread yeast (yeast divide and multiply and so only a few starter yeast are required). I change the yeast mixture when the rate of bubble production slows down noticeably (and this seems to be about every two weeks, although I do not keep to some timed schedule but rather I judge by bubble count). Plants require a relatively consistent co2 level (whatever the level is, it should be consistent, as in consistently low or consistently medium or consistently high, so the plants can physically adapt). On the ten, twenty, and fifty five gallon tanks I am running airstones to blow off some of the co2, since I find that without this step to much co2 is added to the water, and it is best if everything is consistent in the tank (low light, low co2, lower rate of fertilization). Even with the air stones gently agitating the surface of the tank, the co2 pushes down the PH on the tanks, but only enough to indicate about 10ppm of co2, which is a low level and about what I want. On the fifty five gallon long I used one of the motorized co2 reactors (a water pump sitting on top of a clear plastic cylinder with a sponge at the bottom. This device is extremely efficient at dissolving co2 bubbles completely into the water (the bubbles cannot rise as they are constantly kept dancing around in the cylinder by the flow from the water pump, while the sponge becomes saturated with co2 enriched water. Even with the airstone working this device pushes down the ph of the tank a little more than I might want. I keep the water pump on a timer, which shuts it off over night to prevent over night co2 spikes (since plants release oxygen into the water when the lights are on, and then release co2 at night while the lights are off, and therefore it is not required that this device also be pounding co2 into the water during the lights off period). On the twenty gallon tank the depth of the substrate was kept shallow to prevent release of hydrogen sulphide gas. Consequently the plants have depleted the soil and require regular fertilization. I use a pellet making kit, a lump of clay dug up from three feet down, and PMDD (pre-mixed fertilizer compound containing all the major and micro nutrients). When I need to wet the clay in the pellets I use the liquid fertilizer I purchased instead of water in order to use up these compounds. I use a pellet applicator (a type of plunger) which then fires the dried clay pellets about two inches down to the plants roots. The flat clay flakes in the fifty five gallon aquarium are ideal for holding nutrients in clay pellets below the surface and out of the reach of algae. I know this to be true for I do tests for the presence of iron in the water (an indicator element) and it is practically non-existent, which indicates that when spot fertilizing with these clay pellets, the fertilizer is effectively kept out of the water column and down at root level where I want it.