Sump/display turnover rate

the only proper way to determine over flow amount is to measure it. Get a 1 gallon pitcher and have the return fill it. count the seconds it takes to fill and then convert that to gph... Manufacturer numbers can't take all the head loss and like in to account. Also pumps slow down with out cleaning.

The flow through rate in the sump is never specified by skimmer manufacturers that I'm aware of, do you know of a skimmer that specifies this number?

 

Bingo, you hit the nail on the head. I call the flow measuring process you described as "bench testing the sump return rate of flow." When bench tested my return I built a mock up of the plumbing so I could measure flow at the actual "head" hight (about 5 ft.) You can get around this by catching a small amount out of the actual in tank return (flex loc etc) and doing the math. Stay away from cheap pumps, they will diminish in power be more prone to leaking electrical current (in the long run.) The best return pump I like is the Tunze variable speed dc motor electronically controlled. It is the only one on the market like that. You can buy from a sponsor for about $220.00.


Regarding parameters of flow rate for the sump and for the skimmer Reef Dynamics (Euro Reef) is the manufacturer (Jeff) who helped me out balancing my system by having these specs in all their literature. Everything is heavy gauge heat welded sheet PVC and cast acrylic and Made in USA. The skimmer pumps are german and Italian.
Balancing out your sump system with water depth, flow thru, upper tank size and skimmer dynamics is KEY. Skimmer should be wide as possible, easy to clean, and fit nicely in your sump cabinet.

P.S. You might want to take a look at the new Tunze skimmer that does not filter plankton(Tunze website.) I didn't have time to check it out yet but it looks interesting otherwise.

 

My return pump is Italian.

the Marineland 5500, quiet, stays clean, and always restarts after shut down automaticallly. At my 3.5ft head, with 90 degree pvc bends in the return, I'm still conservatively getting about 800gph return. That's thru the sump, on my 125 reef.

Obviously by the articles recommendations, thats way too much.

 

Depends on how your skimmer is designed. My LFS #2 swears by 900 gal thru the sump and further states that some skimmers are designed accordingly. I have a $340.00 IWaki RLT 30 for a conversation piece. Wanna buy it? I'll sell it real cheap. Like new.

 

Nice U-Tube. Watch out with the powerheads. I just discarded a two year old Koralia 2 as being suspect of source of contamination from the steel shaft (some grades of steel are toxic when corroded) and the flexible ends for the shafts (I don't think they are pure silicone, many plastics corrode leaching toxic material.) I'm replacing it with a Tunze 6095 w/backup power safety switch.

If that were my tank I would point the powerheads parallel to surface, just low enough to avoid vortexes. It's all about surface circulation and oxygen exchange. I would also run two power heads on each side. Except for PVC, I would make sure all plastics in sump are food grade. Plastic can be nasty in long run.

 

Thanks for the feedback on my tank. I often move my powerheads some. The surface circulation/and 02 exchange on my tank excellent. This is b/c about 20 inches of surface water are constantly being skimmed off and into the rather large opening(6&3/4 in. diameter) intank surface skimmer you saw on the video. Just my sumjp alone runs AT LEAST 800 gph from the 3/8 of an inch of my surface water being runnoff into my intank skimmer- thru the sump, (the PS- with all those bubbles are excellent air exchangers. If I aim the pwer heads at the surface, too much surface turbulance.
I learned early on that it's healthy for the live rock to have the flow directed at them some. I've got some aimed directly at my sps, and my lps and softies get a little less flow. All in all there are no real dead spots in my 125 DT.

 

At that price you can easily move on if and when ready. Watch out for growing noise, shaft steel and shaft rubber stopper contamination. That's a few years out and then you can easily buy the apple of your eye.;D

 

I the concept.
I see what you mean. The length of your tank is driving the positioning
of your powerheads to reduce deadspots. If you had four powerheads you might be aiming parallel to surface, just low enough to avoid voretex. Parallel to surface is what I meant to say earlier, not up.

 

I have tried high flow (10x) through the sump all the way down to about 1x and i feel 3x is just about right, I like to match the water draw of the skimmer to the flow through the sump, I do get better results with the amount of organics that the skimmer would remove. I have seen a sump design where the tank water is first brought into a conical settling tank and then to a traditional sump, the settling tank is where detritus can accumulate in the bottom where you will have a valve and with a quick turn of the valve the detritus can be removed with out siphoning.....I think it was a pretty slick setup

heres a link to the tank that was used

35 Gallon Total Drain RectangleTank - SP0035-RT