Filter inlet and outlet positions on a 125

i would think on the short sides pointing at each other.buy hey!i dont know that much about circulation and that ''stuff''. i am not going to lie there are many other people better suited to answer this question.but im trying to help a little bit

what are you trying to accomplish? some fish would enjoy a lot of current, others not so much. you could do both outlets at diferent levels on one side, inlets at the other, and create a river effect. You could have them staggered like you said for a simmilar effect, but with a less uniform current, although I would swap the inlets so one was pushing into the other.(just makes aesthetic sense in my head to pull water from the middle and push it to one side and vice versa) Ive become intrigued lately with the idea of running a can outlet teed into either side of UGF plates with the pickup mid to high. that would be better with less current happy fish, but with a larger tank, and 2 cans, could work with one pushing the ugf and another pushing from 1 side with both inlets to the other side. That would be less current but with the rugf, would keep the substrate cleaner. that however wouldnt work with finer substrates. I guess there are a lot of variables

I have two Eheim 2217s on my 125 gal. I have both spray bars on the left side up high, pointing toward the other end and both intakes on the right side down low with sponge prefilters on them. My tank is set up as a high-current tank for gobies and hillstreams so along with the spray bars there is a manifold under the sand with intakes on the left and powerheads on the right. There are also three bubble curtains along the back and more powerheads up high on the left side.

Mark