Hello Guys and Gals,
I have created a planted tank with no filtration, some water movement via an air pump, green water and a host of living things including planeria, copepods, daphnia, pond snails, trumpet snails, lots of shrimp, and at the very top of the chain I have 4 ember tetras (the tank's Terminators). The tank is not heavily planted but does have growing plants in it and the plants compete with a very nice bloom of unicellular algae. Running a tank like this has lots of things to consider. The tank is a 25 gallon cube and I change out about a quart of water a day. No temperature controls and the tank is right up against a bunch of large windows which get LOTS of sun but no direct sun (I get 6 degree temp variations throughout the day). There is no external lighting. Just a little air pump to move some water around and man is that necessary. Turns out that plants require oxygen at night and the algae bloom is demanding! Java moss at the bottom of the tank too and a couple of rocks. The ph is 7.1 and good parameters all around. Water is CLEAN. I have had this running now for about 3 months and everything looks good. Shrimp buzz about all day, infusoria visibly abound and the 4 tetras play around all day and appear to be very healthy and great color. The only nutrition that I have introduced into the tank is a pleco wafer once a week which i throw in like a pill. I used soil as the base with some gravel here and there. I have an eggshell in there as well. I really can't see into the tank because of the algae, but i can see enough to know what's going on except a good 2 inches from every side. At the top, I have wolffia which was recently introduced and doing well.
My question relates to the nutrition. The way i'm working this all hinges on the unicellular algae bloom continuing to bloom within reasonable limits without fouling up the water with too much detritus or too little nutrition allowing the algae to disappear and starve the infusoria. Does anyone know if I can maintain this green water with say a 1/4 teaspoon of flour once a week? Anyone ever dose a tank with flour? Any ideas, insights and tips about the tank setup and nutrition would be great! I like what i have going, but don't want to suffer a crash from unforeseen dynamics. It seems to be working, but it could be just luck.