Which return pump should I use for a seahorse tank?

[airq33]

I have a 37 gallon column tank that I am setting up for a pair of tank-bred seahorses. I plan on building a 20 gallon sump/refugium for the system as well. Since they prefer low flow, I'm trying to decide on the best return pump to use for the system. I've narrowed my choices down to the Quiet One 1200 (296 GPH) and the Quiet One 2200 (581 GPH). I think the 2200 would create too much flow, but that could be remedied easily with a ball valve. I would prefer the 1200, I'm just concerned that it may not be strong enough. Any ideas?

[hydroid]

Although you want gentle flow throughout most of the tank, seahorses do seem to like areas of greater flow ... they will swim and play in it. Avoid stagnent areas where there is no flow though.

The popular rule of thumb is 3x - 6x tank volume turnover. I've found with taller tanks, you want near the higher end of that range. Also, the amount of height the water must travel, greatly affects the final flow rate.

The 1200 has a flow output just under 200gph at 4' of head. It drops sharply as it goes above 4'. If you have 4 1/2' feet of head and some 90 degree elbows or other flow resistance, your actual flow could drop near 100 gph. Not enough imo. If you have no more than 4' of height and a straight path to the tank, the 1200 would work great.

The 2200 has a flow output around 350 gph at 4 1/2' of head. You could get away with this, imo, as long as you distributed the flow ... say with a spray bar.

Bottom line, if you have a tall stand (30+ inches) the 1200 might not get it done. If you have a short stand, the 2200 might be too much.

HTH

[hydroid]

Oh, using a ball valve to restrict flow can cause back pressure on your pump, making it work harder.

If you really want to off-load some of the flow, use a proportional diverter valve. With it, you can direct a portion of the flow in another direction ... like back into your sump.

Just a thought

[craiglanda]

<a href=showthread.php?s=&postid=11117851#post11117851 target=_blank>Originally posted</a> by hydroid
Oh, using a ball valve to restrict flow can cause back pressure on your pump, making it work harder.

If you really want to off-load some of the flow, use a proportional diverter valve. With it, you can direct a portion of the flow in another direction ... like back into your sump.

Just a thought
Thats exactly what i do and it works great! it also allows you to have great attenuation of the water flowing back up in the main display and as hydroid said it relieves back pressure on the pump.

[airq33]

Thanks for the advice everyone. Where can I find a proportional diverter valve, or did you just plumb in a tee to divert the water back to the sump?

[craiglanda]

just plumb in a tee and divert the weater back to the sump

[hydroid]

You can create a diverter valve with a pvc tee and a ball valve on the leg going to the sump. Adjusting the ball valve puts more or less flow to the sump ... the rest goes to the display.

[pledosophy]

I'd go with a 2200 split the return with locline in a few directions,a nd you'll be good. JMO