I am seriously looking at a 75 gallon with built in overflow (used) for a sweet price. I'm assuming the overflow means installing a sump - this is not included in the package. If you run a sump, do you like it? What are the benefits and pitfalls? How hard is it to install one? I've been looking at YouTube videos but they are all DIY. I'd be prepared to purchase a commercially made one or make my own. I saw a used Aqueon sump from another seller but have no idea how to size one or how difficult they are to put in. Any thoughts or advice appreciated!