It's a pond pump. The reason why is it outputs 2400 GPH with 0 head. It outputs 2000 GPH at 60 inches head height, which is what I estimate you'll have. I figure you'l have a 30 inch tall tank, on a 30 inch stand, so you'll have 2000 GPH output. Probably a little less than that.
That calculates to around 8 X turnover rate for a 240 Gallon tank. So, that's what I'd recommend. You might wanna go with a Max-Flo 2900, though, for the same price. Either way, you'll probably be alright.
It's a submersible pump, so it'll go inside the sump, so you don't have to drill the side of your sump like you would for an external pump.
And I have 2 of them on my tank, and I've had no trouble with them for 2 years now--so they're reliable.
This is the pump you're talking about right?
https://www.amazon.com/Laguna-Max-Flo-Electronic-Waterfall-Filter/dp/B000HAU4RW