Question about maxspect gyre
 

What would be a better pump the max spec gyre 230 or 250 for a 75g tank?

Probably the smaller of the 2. I have the older xf150 (think that's the model) , it creates quite a bit of flow in my 6' tank

I have a 130 in a 75g (3'x2') and can't go past 40% before it's way too much for my LPS.

I am running two 230's (actually) a 130 and a 230 on my 75 gallon tank with the new controller. They work great. This is where these units really shine. I think the 250 would be two strong from one side. I doubt you would be able to run it 100%.