View Full Version : What Size Pump?

04/17/2008, 03:22 PM
Hi all, i'm setting up a 125 gal. tank and will like to know what size pump will best in terms of GPH?. Thanks

04/17/2008, 03:29 PM
on my 120 I'm personally going with a reeflo snapper, and with a 4' head it's around 1800 GPH, which is good enough for me

04/17/2008, 03:42 PM

04/17/2008, 03:43 PM
i was told it should be about 1000 GPH..

04/17/2008, 03:44 PM
Need more advice please...

04/17/2008, 03:52 PM
You mean a return pump? How big is the sump? In general, a return pump should be 3 - 5x display size after headloss, so 375 - 625 GPH or so. For a powerhead or closed loop pump, a lot more than that depending on what corals you keep.

04/17/2008, 04:08 PM
125gag display and a 40 gal sump..

04/17/2008, 04:41 PM
are you on a budget? is it a "standard" setup or is your sump in a different location than your tank like in the basement? Is your concern temp, noise, head pressure?

04/17/2008, 07:40 PM
No budget, it's standard set up, temp may be a little concern. thanks..

04/17/2008, 09:28 PM
I use a Mag 9.5 for my 125gal FOWLR. It works well for me.

04/17/2008, 10:23 PM
Mag 9.5 add heat to the water if just simply drop them in. However, the manufacturer does NOT recommend this pump to be used externally. Very good performer though. The 3 MDQX-SC from Little Giant is pretty good performer, but it runs rather warm. Blueline (panworld) 50PX-X has almost identical flow rates as the Little Giant except that they DO run cooler and supposedly quieter.

Sequence Snapper, obviously being at the top of the list but maybe to much flow through the sump for your skimmer to catch everything passing by.

Oh, the reason why I asked about the NOISE issue is because Blueline has a VELOCITY series pump or Poseidon pumps (same thing just named differently) which are DEAD silent but add heat to the water.

04/18/2008, 02:34 PM
So you think Little Giant is the one i should go with?

04/18/2008, 03:39 PM
The 3 MDQX-SC from Little Giant is not very quiet IMO.
The panworld may be quieter but no experience.
I replaced my 3 MDQX-SC with a Gen-X 40 and it is much quieter.

04/18/2008, 05:06 PM
thanks, more advice please..

04/18/2008, 10:03 PM
GEN-X 40 has almost exactly the same flow rate as the LG 3 MDQX-SC. LG uses 0.9 amps and GEN X a little more electricity at 1.2 amps. I run my LG in my room and doesn't bother me...it's just a slight humming noise. However, like I mentioned before Velocity/Poseidon Series pumps are DEAD silent and use 1.3 amps but add heat to the water.

04/19/2008, 12:43 AM
What other flow devices are you going to have in your tank?

For a return pump the Genx mak 4 is great, but depending on your overflow setup and sump config it could be more flow than you need, but you will still need lot more flow in the tank depending on what corals you want to keep.


04/19/2008, 08:12 AM
It's a RR tank, with a couple of tunze 6060 and two 6025, 40 gal breeder sump, and it will be mix tank.. Thanks..

04/19/2008, 08:50 AM
Think of the basic purpose of the sump. A place for filtration, so in theory, your return pump can be no bigger than the gph rating of your skimmer.

Balance this against, are you relying on other circulation in the tank (CL or PHs) or is your return pump is to provide it. The other thing to consider is the sump going to be a combined refugium, if so need to determine how much turn over you want there and if the GPH rating of the skimmer/ return pump, going to give it.

04/20/2008, 08:03 AM
das75 thanks for the info, i'll keep it in mind...

04/20/2008, 08:36 AM
I'm not going to run the snapper at full power, it'll have a tee and a ball valve on the output and back to the sump so I can adjust how much actually goes back to the display, like this http://www.melevsreef.com/return.jpg Also, when your max output of the pump is very close to what you need instead of more, you have to be more cautious about the plumbing, such as how many 90's and things like that. With more power you can do what you want, and then open or close the ball valve until the amount returned is just right :)

04/20/2008, 09:16 AM
46fiat, very good info, that's something i'll try to do. i like that...thanks

04/20/2008, 11:37 AM
no problem, glad I could help

04/20/2008, 12:59 PM
46Fiat, can you post some pics of your set up? will love to see it.. If it's too much work don't worry about it.. Thanks....

04/20/2008, 06:24 PM
It's actually a build in progress, I'm getting the pump as soon as my funds allow (being split between several hobbies) but when it's finished I would be glad to post some pics

04/20/2008, 06:38 PM
Thank you so muchhhh, good luck with new project....

04/20/2008, 06:38 PM
Thank you so much, good luck with new project....

04/20/2008, 06:41 PM
good luck to you as well:thumbsup:

04/20/2008, 06:47 PM