My shrimp tank is coming along well (though at this early stage it still doesn’t have any shrimp in it). Since the last installment I have set up my CO2 system, which has considerably improved the growth of the plants. The Anubias, in particular, has filled out considerably and I imagine it will be a favorite place for the shrimp, since its broad leaves will offer them a sense of security. Despite the Riccia exhibiting decent growth, it is not covering the steel mesh; in fact, none of the plants completely covered the rocks or wood they were attached to (not that I expected them to yet).
I have had some difficulty with various aquarium pests that experienced hobbyists likely know well: duckweed, bladderwort, and snails. Duckweed is an interesting “pest,” since some people choose to add it to their aquarium. It reproduces so prolifically that it can cover the entire surface of the water, blocking out light from the plants below. Every time I conduct a water change I simply skim off the duckweed to keep the amount of it in check, keeping in mind that some floating plants do help make the shrimp feel secure. With duckweed, balance is essential.
Bladderwort is a rather difficult pest to conquer, given its small size. I am still working on removing it, largely by physical removal whenever I see it. Stay tuned to my column to find out who wins—the bladderwort or the subwassertang.
Snails can be gotten rid of by depriving them of their food source, which I did by eventually getting rid of the fungus on the Tambora wood (for how that happened, please see my TFH February 2009 column). Remember that the less organic waste in the tank—uneaten food, decaying plant matter, and fish waste—the more difficult it will be for the snails to survive.
Another important consideration, before I add the shrimp, is to keep the water quality high. If too many dissolved organic compounds (DOCs) are allowed to accumulate it is likely that an algae plague will take over and blue green algae (cyanobacteria) will grow. Although shrimp are algae eaters, it is better to prevent the algae plagues than rely on shrimp to clean it up; they are small animals that can only eat so much! Also, shrimp tend to be sensitive to DOCs and can be killed if there is there are too much DOCs when the shrimp are introduced.
Currently I change 30 percent of the water every five days. In planted tanks, with their many tangled roots in the substrate, gravel vacuuming is done rarely because the chance of damaging the plants is very high. Even when siphoning around plants you need to be very careful to avoid, for example, sucking up the Riccia into the siphon. Sometimes I stretch a filter bag or cheesecloth over the siphon to prevent the shrimp or plants from being taken in; it also helps prevent the siphon itself from clogging.
Once I begin to fertilize the tank I will reduce my water change schedule to once every seven days, so the plants have time to absorb the nutrients from the fertilizer. However, during that time especially, I plan to remove as much algae as possible from the Anubias. In my experience Anubias is an incredible algae magnet.