Return GPH matching your skimmer?

tashier · 08-18-2006, 12:36 PM

I'd just like to see if this is a common practice and what data there is to support this theory. A CLS for me at the moment would be difficult and I was planning on running high volume through my sump and overflow.

BGJ223 · 08-18-2006, 01:14 PM

My 60 gallon return matches my skimmer. For my 20 gallon My retrn will be around 250 GPH and my skimmer will be a ASM G1-X (not sure on GPH) so the GPH of my skimmer will be higher. The thing to worry about is the higher your GPH the easier it is for microbubbles to get into the display. I think a CLS would probably be a better bet. They can be done pretty easy. In fact I am going to make one this evening with a spare Mag 5 I have laying around.

Fly Guy · 08-18-2006, 01:41 PM

It does on one tank (by default, not intentionally,) not even close on the other. If i tried to match the skimmer to the sump on my tank with the 100 gallon sump it sim-pl;y wouldnt be enough flow through the sump, as well as cut a couple thousand gph of flow that i like in the display.
I think the skimmer is going to grab and process the same amount of water no matter hjow fast the stream it is taking it from is going. However, i do like to set my sumps up so that my skimmers pick up the water from the drain and release it on the other side so it is skimming new drain water that hasnt just been skimmed. Does that really matter???? Probably not.

Brent Cone · 08-18-2006, 01:52 PM

Quote:

Originally Posted by Fly Guy

It does on one tank (by default, not intentionally,) not even close on the other. If i tried to match the skimmer to the sump on my tank with the 100 gallon sump it sim-pl;y wouldnt be enough flow through the sump, as well as cut a couple thousand gph of flow that i like in the display.
I think the skimmer is going to grab and process the same amount of water no matter hjow fast the stream it is taking it from is going. However, i do like to set my sumps up so that my skimmers pick up the water from the drain and release it on the other side so it is skimming new drain water that hasnt just been skimmed. Does that really matter???? Probably not.

I agree! JMO!
Brent.

PelagicMagic · 08-18-2006, 01:54 PM

skimmer 1800 gph

return 3600 gph

tashier · 08-18-2006, 02:44 PM

Thanks for the input so far...

tashier · 08-18-2006, 05:00 PM

Anyone else?

Geoff · 08-18-2006, 05:04 PM

i feel that water going by the skimmer is wasted flow through the sump. there is a much greater chance that water will not be skimmed for a very long time if it is able to always go by the skimmer. i guess the same can be said for a CLS, but the percentages will be better if all the water that goes through the sump is processed instead of some.

also the greater the flow through the sump the harder it is to keep the tank quiet.

G~

tashier · 08-18-2006, 05:19 PM

Quote:

Originally Posted by Geoff

i feel that water going by the skimmer is wasted flow through the sump. there is a much greater chance that water will not be skimmed for a very long time if it is able to always go by the skimmer. i guess the same can be said for a CLS, but the percentages will be better if all the water that goes through the sump is processed instead of some.

also the greater the flow through the sump the harder it is to keep the tank quiet.

G~

Hmm, interesting, but here is my take on it.

I have a 120g. Let's say my skimmer does 500gph. That means that at best, if I funneled ALL the water through the skimmer , I'd be skimming my water 4.16 times per hour. BUT since the water goes into the sump and churns around and the skimmer may or may not pick it up, that number is probably smaller. Do we think that the total percentage of water that gets skimmed in the tank increases by slowing down the water going by the skimmer? I'd say if you slow it down you may actually end up reskimming the same water in the sump correct? Possibly leaving more unskimmed water in the tank itself? That's how I'd perceive it? I darn well could be wrong.

Sean

cobray · 08-18-2006, 05:36 PM

I say just keep the water moving as much as possible and everything seems to work out just fine.

tashier · 08-19-2006, 02:13 AM

Hmm, there's got to be a few more people on TRT with a sump and a skimmer. Isn't there???

Tim224DT · 08-19-2006, 10:11 AM

My skimmer pump is a mag7 and my return pump is a little giant 2 series around 440 gph on my 72gallon tank.

Personally i think a kick butt skimmer with a good pump and slow flow in the sump is better. IMO the slower flow in the sump will allow the skimmer to skim that water really well before it gets pushed back up into the tank.

I know other disagree with my thoughts but i know many that do.

Tim

three90s&125sump · 08-20-2006, 01:27 AM

Skimmers are no where near 100% efficient. They are more like 60 to 80% and that is for really good skimmers, a seaclone is about 10% efficient and a really good very powerful recirc might be 80% this could easily be tested with a drop in style TDS meter for readings before and after the skimmer.

My return pump will actually out flow my skimmer but I have a ball valve on it to adjust it so it doesn't. I have about 2900GPH going through my skimmer and about 2600GPH going through my return pump. These are just guestimates.

I (like fly guy) also have my sump set up so the skimmer deposits the water into another chamber and that chamber over flows back into the skimmer chamber to be run back through the skimmer. I want to keep the recirculation through the skimmer to a minimum but I (like Gee-Off) also don't want to risk having the water flow back to the tank with out being processed. I think it is a waist for the water to go to the sump with out being processed.

So in my system it is impossible for any water to be returned to the system with out first being processed by the skimmer and I feel with ~2600GPH (~7.5X total water volume) going through my sump and ~2900GPH (~8.3X total water volume) going through my skimmer I am getting the best use of my sump and skimmer as I can get.

tashier · 08-22-2006, 10:36 AM

Viv · 08-22-2006, 01:32 PM

Maybe it's got more to do with how your sump is set up. My old sump didn't have a separate compartment to return skimmer water and it picked up the same water that mixed with what was in the sump already. I'm picking up a new sump which will have two compartments, one that the skimmer pump will pick up the overflow water and a second compartment that will take the processed skimmer water. I think that depending on what you have may make the difference. Did that make any sense?