return pump size

[reedman]

A bit of a strange question for you all....and I have looked around and can't seem to find an answer....though I think I know it.

For my return pump, can it be too small? As long as it produces some flow will going small cause any problems? I am looking at using an eheim 1250 that I have laying around, but this only 300gph (less head losses). This seems pretty low to me, but then again I am not using the return as part of my flow anyway. I am thinking this should make the return very quiet as well.

A little info on the system....80gallon display, 10 gallon fuge, 10 gallon sump. 1.5" overflow plumbing from tank to fuge then to sump, so no restriction at all. I currently run a mag 7 return pump (but it's louder than I like). I run a vortech for flow in the tank and it is plenty for my softy/LPS mix (and a few SPS).

Let me know your thoughts please.
Thanks,
-Reed

 

[vinny2261]

Your 1.5 inch overflow plumbing can handle at least 900 gallons a hour drain. If you go to a oversize plumb coming out of your drain you can sometimes drain a little more. With the siphon that is created you maybe able to flow more through the system. 300 is really low for return pump especially once you figure in for head loss. I would probably double check on what the head loss is going to be to see if this will be enough flow for you. Since your fudge and sump are pretty small a lower flow rate may be better in your case. If you have to much flow it will "wash" everything out of your sump and fuge and your system will not receive the benefits of the filter.

 

[roblou]

FWIW, I think you'll be ok with the smaller pump...

 

[trido]

IMO you can have too small of a return pump. Seems you can have a 100X turnover in your display but if you arent gettin enough dirty water to the skimmer it wont have a chance to do its job. I feel that I dealt with that for over a year.

In your case, Id shoot for closer to 600GPH.

 

[TJL]

Hey Reed,

I have a Rio 2500 sitting around you could hook up to see what a little extra flow would be like ( its just my salt mixing pump ) and don't use it much.

Todd

 

[reedman]

alright....I get what everyone is saying....I think.

Duane, I know what you are saying for certain and that is my only concern. I need to get all that crap to the export area otherwise I will have a really clean sump and not a clean system.

Todd, I have a mag 7 on there now that is plenty sufficient for my needs, so thanks for the offer, but no. I really just want to make use of the eheim I have if I can. I thought it was a 1260 which would have been perfect, but it's a 1250 which is pretty low flow.

I may hook this up to my existing plumbing and see what happens over a short time. If I see a significant drop in the skimmer production/fuge growth then I guess I have my answer.

Thanks again everyone!

 

[TotalVapor]

Double post sorry - please delete

 

[TotalVapor]

Return pump - two to five times turn over of the tank per hour.

Also should be matched to a your skimmer.

If you keep it two or three times turn over of the rating of your skimmer, if you purchased your skimmer based on tank size, you will be allowing the skimmer to work smarter not harder.

With a 80 gallon display a smaller pump that is rated at 300 GPH should do you just fine. Remember to take off some GPH based on you head pressure.

 

[reedman]

Return pump - two to five times turn over of the tank per hour.

Also should be matched to a your skimmer.

If you keep it two or three times turn over of the rating of your skimmer, if you purchased your skimmer based on tank size, you will be allowing the skimmer to work smarter not harder.

With a 80 gallon display a smaller pump that is rated at 300 GPH should do you just fine. Remember to take off some GPH based on you head pressure.

Interesting! Can you expand a little on this please....

My skimmer is an Octopus DNW200 recirc with a maxijet 600 feed pump.

I hear you on the head pressure....I know I will lose some there.

 

[bigblue141]

FWIW, I would look at bumping up your sump to a 30gal or so. With a bigger sump you can use half of it as your fuge, plus you get the added bennie of larger total tank volume.

I'd put an 800 GPH pump for a return which should give you around 500 GPH after head loss, elbows, etc. You have to get your water to your filter system in order for your filter system to work.

 

[reedman]

just to be clear, the sump is a 30 gallon tank that holds about 10 gallons of water when running. The fuge is between 10 and 15 gallons (I think). Water volume is not a concern of mine, though I understand the point being made. Space limitations dictate what I can and cannot have.

Only question on the table is if swapping the eheim 1250 into the existing setup will hurt my setup.

 

[TotalVapor]

Simple answer is No it should not hurt anything since you only have a 80 gallon tank.

 

[TotalVapor]

Interesting! Can you expand a little on this please....

My skimmer is an Octopus DNW200 recirc with a maxijet 600 feed pump.

I hear you on the head pressure....I know I will lose some there.

You have a PM

I read your skimmer is an Octopus DNW200 recirc with a maxijet 600 feed pump.

The whole point of a Recirc Pump on a skimmer is to give the skimmer more time to work with the water. Thus pulling more proteins out of the water.

With a Recirc skimmer your feed pump should be 1 1/2 times the volume of your system. So your system should be around 100 to 110 gallons total volume since you have a Maxi Jet 600 feeding it.

I thought you had a in sump skimmer and that was why you were worried about changing the return pump.

 

[mfinn]

I'd give the eheim a shot.
As long as you are getting surface skimming with your overflows, it should be fine.
With a vortec for flow, the detritus in your tank should remain in suspension untill it hits the sump, where, when the water slows down, it will drop and accumulate.
Where it can be syphoned out during water changes.
Plus slower flow through the sump gives longer contact time for the skimmer and refugium.
Slower flow = less evap.

Like I said first, as long as you get surface skimming from your overflow.