How do I size my return pump

[supersaltlick]

I am looking at several makes for my return pump.
How do I ensure that I have enough power for adequate water turnover? What is adequate water turnover? This will be a 70 gal reef with 30 gal sump. The water will need to travel about 4 vertical feet to display. My LFS recommended mag drive 18 or 24. Is this overkill?

 

[rhino509]

i have 75 gallon with a 40 gallon sump and i use a mag 9.5,it could almost be a little slower for my likings(but my baffles are kinda tall).closed loop would be a nice addition,even though there is extra cost for the extra pump.

note....i also have about 4 verticle feet to display,i softlined the plumbing to the bulkhead so there wouldnt be any elbows to restrict flow{before i had baffles)

 

[UnderCoverDork]

think they have a chart at marinedepot dot com

 

[silverwolf72]

Return flow shoot for 3 to 5X tank volume. Use other ways to increase flow in tank(power heads, closed loop).

 

[laserjim]

Not sure if you have this or know of it, but here is a head loss calculater .You can plug in different pumps to see what you like.

http://reefcentral.com/calc/hlc2.ph...Couplings=0&CheckValves=0&Exits=1&Entrances=1

 

[five.five-six]

<a href=showthread.php?s=&postid=9459644#post9459644 target=_blank>Originally posted</a> by silverwolf72
Return flow shoot for 3 to 5X tank volume. Use other ways to increase flow in tank(power heads, closed loop).

is 10 x too much?

 

[supersaltlick]

So the 3-5 X tank volume applies to all forms of flow (return + power heads + closed loop)?

So if I use a quiet one 4000 I would have about 562gph after accounting for headloss. this is already 5X my tank volume. Doesn't leave much room for adding power heads to costumize the flow. should i use a smaller pump and add power heads?

 

[laserjim]

3 to 5 x is only your sump flow. For whole tank and sump together go 20x or more depending on what your keeping.

 

[supersaltlick]

got it. so the quiet one 4000 is actually about perfect as far as flow goes?

 

[laserjim]

<a href=showthread.php?s=&postid=9460016#post9460016 target=_blank>Originally posted</a> by supersaltlick
got it. so the quiet one 4000 is actually about perfect as far as flow goes?

70 gallon tank x5 =350gph through sump.Some people say the more flow the better.Other say slow flow through sump.The 4000 would be 8x. Im know expert,dont really know which is best slow or fast flow.Depends on who you talk to.

 

[supersaltlick]

OK. I was thinking total system volume (70g tank + 30g sump =100g total). If I understand correctly it should be 3-5 X display volume which would be 350gph. Does this number need to be adjusted based on the actual water volume as my live rock will take up some of this total space and it will not be all 70g water?

 

[AZDesertRat]

Look at an Oceanrunner 2500 or 3500 or an Eheim 1260 or 1262 for a return pump. Quiet Ones have restart problems plus I had one burn up on me and electrify my tank. Mags are power hogs, create more heat then any other and are noisy.

5x volume is just a rough estimate but works pretty well in helping to keep microbubbles from travelling back to the display tank by keeping sump velocities down.

An Ocean Runner 2500 should be about perfect for your application.

 

[supersaltlick]

Thanks for all the replies. I think we'll go with the ocean runner 2500.

 

[AZDesertRat]

Drs Foster & Smith had them on sale, I don't know if they still are or not though.