Hello again just me. I cleaned out one of my 75 gallon aquariums today. Just thought I would post some of the things to watch for when you either clean out or set up a new aquarium. Ideally when you do either of the two ,you have to let the aquarium cycle for 3 to six weeks depending on the size of the tank. What's meant by cycling is more or less let the aquarium run with filters or power heads on to establish beneficial bacteria in the tank system and to remove any impurities in the water such as ammonia and nitrates. Pet stores sell products that will help reduce the time it takes when cycling a tank. Sometimes what I will do is use a certain amount of water that was originally in the tank before cleaning and put a certain amount of it back in the tank after cleaning provided that there were no signs of disease in the fish before cleaning. This will help the fish adjust more easily to the tank water when putting them into the clean tank. Keep this important fact in mind when starting a new aquarium. You cannot simply set up a tank and add fish to it right away. Let the aquarium cycle and properly acclimate the fish to the new water and in the end you will have healthier fish.