low flow or high flow through refugium?

[aoc230]

i would do it like this? i don't see a point in running clean water to the sump, maybe i just haven't had enough convincing? sorry don't run with the sheep unfortunately i need reasons on why things are done(rebel lol). if you wanted a secondary filtration put reactors in the return area.. i would run it at only 20-25% flow going thru the refugium section, eventually after the waters run thru the system a couple of dozen times its all the same??? i see it as all the same except your original way is being fed by gravity, no power loss, im huge on that.

so im in the process of redesigning my sump/refugium as i read that it is better to have slow flow through refugiums.

my new plans for my sump/refugium will have two seperate drain pipes. one going to a skimmer section on one side and another drain pipe going to a refugium on the other side. the return pump will be in the center chamber and flow to the refugium will be controlled by a ball valve.

but if slow flow is not required for a refugium it would be much easier to just have my sump set up as skimmer/refugium/return since the drain pipes would just have to be routed to one side.

so im just looking to see the pro's and con's of slow/fast flow through a refugium.

here is a paint diagram of my sump/refugium. its not to scale

 

[aoc230]

It will also allow you to uae a filter sock on the drain line - but that's another thread.

what will?

 

[cdbias2]

Running water straight into the refugium will lead detrius buildup. Sucking that detrius out of your fuge will take many pods with it and add to your maintenence.
Some people have a fuge to aid in filtration of nitrates and others simpley have it for food production(pods) for the DT.
It leads to the old(long) thread of if the skimmer should go before or after the fuge or after.
I do neither. My fuge is above my DT and gravity drains into my DT.

 

[bertoni]

Having the refugium above the tank is an excellent option, IMO. I disagree somewhat that having the refugium first necessarily will lead to a lot of detritus. I didn't have that problem, but perhaps I didn't run the refugium long enough.

 

[seabayaquatic]

At a minimum the flow through your fuge should be 10 times your tank volume per hour. This will keep the dissolved oxygen elevated and help to stabilize your pH. Go with the biggest fuge you can fit under your tank, if not the same size as your display tank. I would move the return pump to the far right side and keep the center section for the algae. The way you have it shown in your drawing, only a small portion of your total water volume will actually get processed an hour by the algae. By keeping the algae in the center, it is in an area where it is constantly being brought nutrients and won't starve.

 

[bertoni]

I would target at most about 3x the tank's volume per hour through the refugium, in general. More will be fine, but can get expensive and noisy. Getting 10x the tank's volume in total flow is fine, but I'd do most of that with powerheads or closed loops, which are quieter and cheaper electrically.

A very large refugium might need a powerhead of its own, but that's not usually an issue.

 

[cdbias2]

I disagree with seabay.
The 10x calculation is for sumps, not refugiums.
Refugiums should have 10x's turnover, but 10x's turnover of the refugium volume, not the tank volume.

 

[Proffugazi]

Well, just to cause trouble, and be a heretic: higher flow through the sump, and lower flow through the "fuge" section. A couple have previous touched on this, but I will put it graphically, because that is just what I feel like doing, because you have to change the flow logic.

And for those that swear by external return pumps as I do:

Jim

I Also like to be a "Heretic" lol I have a med Aquafuge(hang on) with 3" live sand topped with 1" mircule mud then about 4" calcium carbonate rubble on top that. Then I have water screaming lol through at around (i think) 350-400gals a hr that flows thru a ball of cheato(lit by 250w MH) The thinking being with the high flow rate water, will be pulled from the bottom of the live sand. Baffler prevents any thing flying around and works like a charm!