My mom has a 29 gallon with a red tail shark, 2 black skirt tets, and 3 red eye tets. Well algae started to grow on a decoration and I told her it was probaly from leaving the light on too long. Correct me if I am wrong please. So anyays, I told her to buy a algae eater and she did. Now before the bottomfeeder was put into the tank she dropped 2 algae tablets into the tank. Then aout a week later the fish died. So is the cause of death because of the tablets or something else? Any help would be appreciated. Thank you for your time.