Hi I bought a fluval edge tank 6 months ago, I have no problems at all. I bought a 20W heater (not a fluval edge one) which as teh previous response states the wiring goes down the back of the tank, I fill the tank up to top. I have 6 neon tetras and an apple snail will has grown a lot since I added it. I have plants hich have grown very well. The tank looks great and is no problem to look after, the fish are very happy, they do not gulp for air, I think the tank is a great design and my fish have maintained there colours and are happy. You can buy replacement charcoal, foam and biomax filters online from seapets or rocket pets. I am planning on getting two shrimp. I personally would not put a goldfish in the tank but if you do not overstock your tank and you look after the tank as it states you should not have a problem.