This thread has me thinking about doing a small experiment. Not really an "experiment", since I can't set up very many tanks, but I was thinking about the possibility of setting up 3 identical 5 or 10-gallon tanks -- same substrate, same plant species, one type of fish, same dosing regime (if any), same feeding schedule, etc.) -- but have 3 different lighting schemes. The control tank would run a standard 12-hour photo period from 7 to 7. The other 2 tanks would run split photo periods (4 on, 4 off, 4 on, starting at 7 am), but one would be in a dimly lit room, and one would be in a brightly lit room.
The purpose would be to observe the rate of plant growth, algae growth, and fish behavior. Anyone have any thoughts on how to measure/describe these things? Especially "fish behavior". And if you have any thoughts about the design of the experiment I'd be interested to hear them. Might need to do a separate thread....