Ok this is probally a stupid question that i should know but, I have been thinking about getting an ato soon for my tank since im tired of constantly topping off my tank , but i am completely lost as to how it actually works. I have tried to search threads about it but still not clear on really how to do it. Do you buy a kit and just install it? i know a float switch is involved in the sump when it gets to a certain point it fills it back up to the desired water level but that is really about it. Thank you