Refugium delimma: return pump + manifold or stand-alone pump

[Special_K]

Hello reef junkies, here is my situation. I'm planning on a bigger set up with sump in the basement:

1. 120-gallon main display tank in living room
2. Basement sump, 40-60 gallon, 11 ft head to DT
3. 40 gallon refugium, 3 ft head.

Shall I run an eheim 1250 just for the refugium, or size up the return pump and power the refugium through manifold? If I go with option #2, how big of a pump I should get?

Thank you mateys!

 

[mcarroll]

Not a fan of the manifold.

1 pump per task = 1 failure per failed pump

Limited risk.

 

[Smo]

Think you need to establish what your flow requirements are to DT and refugium (5-7 times turnover per hour?), add another 20% or so for frictional losses, then look at various manufacturer's spec sheets to apply head losses. Alternatively, you could drain some of your DT water directly to the refugium, which would maximize nutrients going there.

 

[Special_K]

Think you need to establish what your flow requirements are to DT and refugium (5-7 times turnover per hour?), add another 20% or so for frictional losses, then look at various manufacturer's spec sheets to apply head losses. Alternatively, you could drain some of your DT water directly to the refugium, which would maximize nutrients going there.

That's a good idea. So my pump requirement is 120 x 7 = 840 gph at 11" head, plus 280 gph at 3" head... x 120%....

 

[Smo]

That's a good idea. So my pump requirement is 120 x 7 = 840 gph at 11" head, plus 280 gph at 3" head... x 120%....

Yes, so roughly 1,350 GPH at an 11' head. As an example only...if I read Sicce's chart correctly, their Syncra HF 10.0 Pump (2500 GPH), should pump that amount at an 11' head with a little to spare. Prior to any purchase I would consult a knowledgeable sales person.

 

[mcarroll]

x7 is enough overkill to cause noise and other problems with standard drains.

2x - 4x of return flow is all it really takes to drive skimmers, reactors and such....sounds low, but it's not I swear!

So (160 gallons * 2 =) 320 GPH up to (160 * 4 =) 640 GPH.

If it's a simple return shot up to the tank and fuge, then using a manufacturer's flow curve like you'll find at lifegard, danner or sicce should give you a great pump recommendation.

If you have anything more elaborate planned, or if you want to shoot for that higher flow rate, then I'd use a flow calculator like this to make a better estimate of friction losses:
http://www.freecalc.com/fric.htm

Post here or PM if you want a walkthrough! But in a nutshell, you take the output of the calc and add it to your vertical head number and THEN go to the manufacturer's flow chart. It will account for flow rate, specific gravity, temperature, plumbing diameter and material, et al.

 

[Smo]

Agree, the lower flow rate would be fine. Make up the difference with power heads in the DT. I use BeanAnimal drains. The full syphon is very quiet.

 

[Special_K]

Cool. Good to know! That opened up lots more pump options!

 

[mcarroll]

Agree, the lower flow rate would be fine. Make up the difference with power heads in the DT. I use BeanAnimal drains.

Right on. The Bean Animal (and all the similar variants) were designed more or less to support doing ALL of your flow with the return pump, so they can carry A LOT OF WATER.

That was before powerheads were around and so popular so they had good motivation! Folks nowadays usually just do these types of drains out of worry/for the redundancy/for fun rather than out of necessity.

The full syphon is very quiet.

+1

A plain gravity drain at normal flow rates (about 50% of the drain rating, roughly) is also very quiet.