I have to say ... my 20 long is the hardest tank I've had - and the smallest! Keeping acros, fish, etc.. in such a small tank is a challenge for me. I'm always realizing what I did wrong last week. For instance tonight I was marveling at some new red algae and wondering what could have spiked it.. I think it was because I noticed that my pH had been low and cranked the effluent on my calcium reactor... which raised pH but lowered alk... could this be, or is it from all the food I've been throwing since I've overstocked the tank with fish I shouldn't have? :-X Or is it my relatively new halide/T5 light and all of the above? : Either way... this is a challenge. Do you have a nano aquarium going?