Originally Posted by Niccobacci11
since you bought the 20 gallon short time ago would it be possible to return it? If it is then I think a 20 gallon long sump is more manageable because it gives you a bigger footprint for a refuge, return and spot for protein skimmer. However if it is not possible I'm sure that you can find a way to make an awesome sump out of it. Also make sure that there are no dead spots in the middle of that rock pile. The more flow over the rocks the better because it is you natural filter. so the more surface area of the rocks that is exposed the better.
I've had the 20 gallon for a pretty long time lol. i don't have room for another 30 inch tank next to it, otherwise i would definitely do a 20 long. I'm thinking of just going with the 10, so i won't need as powerful of a light to grow macro algae. i plan to have one section the drain pipe and macro algae, than the middle the skimmer and then the third the return pump