My tank is about 4' deep and with 80 fish in there and it is starting to get a little cloudy. My water chemistry is all good so I' m not really worried about that (ph 7.6 ammonia .25 nitrite 0 nitrate a hair off off 0). the question is does any body have a good solution for seeing the bottom of the tank and/or taking pictures?

My concern is with the catfish, I can't see them and the only way I have found to determine thier health is to shine a flashlight in there after dark and they move a way from it. haven't found any floaters or ones that don't move away from the light so I am assumming they are all good.

Any help would be appreciated!