125 Gallon Reef

Between the choices of lighting you have listed the T-5's would be the best, however, Metal Halide are better. SCWD's are only rated to run i believe up to 1400 GPH so if your planning on putting that 2000-2500 GPH pump on the SCWD good luck because you would be buying ALOT of SCWD's. IMHO i would run 2 SCWD's with that tank and have one pump rated at around 1200-1300 GPH run both. Then you can have an alternating current the whole length of the tank. As for the 300 GPH pump your not going to get much done with that. what im trying to say by that is its hard to push that ammount of water across 6'. Your better off getting a few powerheads rated for 500-800 GPH and alligning them along the back of the tank to create a cross motion of water. I hope this helps, If you have anymore questions please ask.

you wont need a pump in the sump just for flow. The water that is returned to the sump from the tank will create all the flow it would need. And yeah one 1200 GPH pump on the SCWD's would be fine. However you would still need more flow that just what the SCWD's give off thats why i said you would need atleast a few powerheads rated at 500-800 GPH as well.

i agree with USC on this. and for some good pumps/powerheads for additional flow give Hydor Korallia pumps a try. they work beautifully

Well the great thing about SCWDs is that they dont need to be in the tank so you can plumb them to work from behind everything. That 1200 GPH pump would work not only as the pump for the SCWDs it would also work as the return pump from the sump. In addition to the SCWDs though you would need atleast 2 more pumps along the back of the tank to create more water current. In other words that 300 Gal return pump wouldnt be needed, it would be a waste of money. I will try to get some pics of the SCWDs on my tank and of the other powerheads also used for circulation in the tank if you think it would help.