MP40 or MP60?

[Charterreefer]

It's an SPS exclusive tank. I have MP40's currently. I was wondering just how much of an improvement the MP60's would contribute to overall flow in the tank (I have a 250 gal DD 5'x36"29" high). My thinking would be to run them a bit slower than the MP40's thinking that they would move a larger mass of water. I would rather move a larger mass a little slower than cranking up the 40's - thinking that this would be less concentrated producing less damage to corals directly in line with the main flow. Any thoughts? Has anyone made the switch and what have you noticed? I'm I on the right track with my thinking?

 

[Husker]

I would definitely go MP60 for a 5' tank. I run an MP60 on my 55 gallon display refugium/seagrass tank (seagrasses like SPS levels of flow) at about 50% on nutrient transport mode. It isn't kicking up the sand or anything, but is giving pretty good flow if it is on the direct opposide side from the overflow (meaning the suction of water over the overflow contributes to some of the water flow). I ran an MP40, MP60, and MP10 on my 40 breeder and was never impressed with the flow. Granted, I had quite a bit of rock and some of the SPS colonies were getting larger. I have a 5' peninsula tank now, so I only wanted powerheads on one end. I tried the MP60/MP40 combo because I had it, and I wasn't impressed. I switched to 2 Tunze 6105s and they are hitting the end of the 5' tank with some serious velocity.

It sounds like you have multiple powerheads, so you are probably good. In my experience the MP60 flow is 3 or 4 inches wider than the MP40 and gives you an extra foot or two of reach. If you have a tank full of MP40s, the MP60 would probably add quite a bit. I just wouldn't expect it to span 5' with too much gusto.