Yet another refuge/sump approval request (image)

[mooner]

I have built this from a 20 long and will try to get it in my system in a week or so. I have some of the parts on order so I still have time for edits. I am going to distribute the 500 GPH feed via two outlets in the main (44 gallon). All plumbing will be 3/4" PVC and will feed back thru a 600 GPH rated overflow box.

I plan on allowing most of the return flow down "Return B" to keep flow thru my fuge at a minimum.

The red circles are large perforations (drilled with a 7/16" bit). I calculated the total surface area of the perforations in the fuge wall to be 1.7 sq. in. and the main baffle to be 3.26 sq. in. Now, I assume that those surface areas are plenty to flow ~150 and 500 GPH respectivly. I want to flow about 150 GPH through the refugium (return A) and the rest through return B so all of the water will have to go thru the baffle perfs.

The other baffle will be for additional air bubble reduction.

I plan on keeping the depth of water in the pump/skimmer area about 4 - 4.5".

The pump is a Mag-Drive 5.

Ideas? Flaws? Problems?

Thanks.

 

[PeeJ]

mmm seems if ur overflow is rated at 600 gph, and your return pump is only 500 gph at 0' of head, youve got a big problem....

 

[Anonymous]

I like your setup. I had a fuge that worked perfectly but my tank was not turning over enough so I got a more powerful return pump. This minor change caused my fuge to not work well anymore. I had to drain it and add a baffle (the same baffle I'm recommending to you).

I worry about water dumping in and disturbing your sand bed (or mud) with this set-up. I would add one more tall baffle (not all the way to the top though) to slow down the water from A.

Decide how deep of a sand bed you want if your fuge, add 1", and then drill holes at that point. That way MOST of the water from overflow A will enter the fuge at the bottom, raise up through your macros, and then go back to the tank. Obviously, if the flow is high enough, some of the water would go over this first baffle, continue over your fuge, and go to your skimmer and return pump.

Just a thought.

 

[mooner]

I like your setup. I had a fuge that worked perfectly but my tank was not turning over enough so I got a more powerful return pump. This minor change caused my fuge to not work well anymore. I had to drain it and add a baffle (the same baffle I'm recommending to you).

I worry about water dumping in and disturbing your sand bed (or mud) with this set-up. I would add one more tall baffle (not all the way to the top though) to slow down the water from A.

Decide how deep of a sand bed you want if your fuge, add 1", and then drill holes at that point. That way MOST of the water from overflow A will enter the fuge at the bottom, raise up through your macros, and then go back to the tank. Obviously, if the flow is high enough, some of the water would go over this first baffle, continue over your fuge, and go to your skimmer and return pump.

Just a thought.

Very good points. I was planning on creating a "U" shape on the end of my return with two 90 degree elbows to redirect the water flow back upward from near the bottom of the fuge (about 2" from the sand bed). But instead I may consider a baffle as you described. Thanks!

PeeJ...not sure what your point is. The 600 GPH is a max rating but it will return only what it is fed. I am well below the rated output so unless I am confused about your point I think I am safe here.

 

[reefann]

PeeJ...not sure what your point is. The 600 GPH is a max rating but it will return only what it is fed. I am well below the rated output so unless I am confused about your point I think I am safe here.

Exactly, there is no problem here. If it were the other way around you could have a problem. I would recommend to anyone that you should have ball valves and those disconnect things, at your retun pump to make maintenance much easier.
If I were you I would put the baffle in instead of the U just so the water does not have to fall as far and make noise.
Otherwise it looks fine to me.
good job
JJ
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[PeeJ]

true true....i guess misread...heres a tip...dont eat only peanut butter and pepsi all day

 

[Anonymous]

heres a tip...dont eat only peanut butter and pepsi all day

Hee, Hee. I'm afraid to ask.

 

[parvo]

I just built a 20l refugium/sump I have my baffles on the tank drain side. You want to have enough time for the air to diffuse out of the water before you return the water to your tank. If your pump sucks air you could possibly supersaturate the water. With the baffles by the return you are bound to get some air down in the water column as it flows over the baffle

 

[parvo]

here is a sketch of what I would of done differently

 

[mooner]

hystrix,

Thanks. Looking at your drawing I am afraid that might be a tad difficult to construct!

I think that if I get air problems I will attack with foam and perhaps one more baffle. Keep in mind that in my setup that the water level on the skimmer/sump side is only 4.5"

Here is a pic of the final sump/fugium.

 

[parvo]

Your biggest problem with air may come from the protein skimmer effluent.

 

[parvo]

Depending on the flow you are probably going to need to drill more holes

 

[mooner]

Beta testing will begin in a few days.

 

[John N]

mooner:
One mild problem will come from the possiblity of your return pump stopping from an electrical outage.

Given the height of the holes in your going from your refugium to your return area, you are not leaving much excess capacity in your sump for the drainage that would happen from your tank into your sump. What I mean by this, is that if your return pump shuts off, you will still have water flowing down out of your aquarium until the siphon breaks in your overflow. You should leave enough room in your sump for this to happen (because it may and will...)

Just my obeservation...

 

[mooner]

mooner:
One mild problem will come from the possiblity of your return pump stopping from an electrical outage.

Given the height of the holes in your going from your refugium to your return area, you are not leaving much excess capacity in your sump for the drainage that would happen from your tank into your sump. What I mean by this, is that if your return pump shuts off, you will still have water flowing down out of your aquarium until the siphon breaks in your overflow. You should leave enough room in your sump for this to happen (because it may and will...)

Just my obeservation...

Understood.

I should have (from guesstimation) about 5 gallons of emergency "fillable" space for an outage. That means that unless the amount of water that is over the overflow spill-over level in my main is more that this 5 gallons I should be ok. I estimate that to be 2.5 inches of water level in my main that can run out after a failure.

Do overflow boxes generally run with this much water over the minimum spill over mark? I suppose that depends on the flow rate into the main and I am looking at 400 or so gallons per hour with head space calculated in.

 

[John N]

Here's a quick calculation to figure out how much water will continue to flow through your overflow box until the siphon breaks.

Take the teeth depth of your overflow box (say 1.5"). Add to it how far under water you plan to put the overflow box. If the top of the overflow is at the water level, only use the amount from above (the 1.5"). Now take the width & length dimensions of your tank (say 48" x 18"). Change all of these dimenions to feet. (4' x 1.5' x .125'). Multiply it all together (4 x 1.5 x .125 = 0.75 and then multiply it by 7.47 (.75 x 7.47 = 5.6 gallons extra area you need in your sump).

Basically in laymans terms, this means that there is 7.47 gallons in one cubic foot of space. You are quickly figuring the surface area and then converting it to gallons.

If you truly are using 2.5" from the bottom of the teeth in the overflow to the top of your water level, you may end up needing to move it up.

One final point on this. If you aren't using a check valve on your return, you will continue to get water coming down until the siphon breaks on the return. I only mention this because many people put the return deeper in the water than the overflow teeth. Basically --- USE A CHECK VALVE, and keep the check valve close to the return pump.

 

[mooner]

John,

You have alerted me to a massive neglection on my part. My feed will siphon back in addition to my overflow box. This will need some serious re-engineering as I had planned to put them at a depth of around 3". I will get a check valve for sure.

Thanks man!

 

[John N]

Not a problem.
I am designing my own sump at this point, and am trying to be extremely careful, given that my tank is on the second floor.
I too have learned from asking questions, and the above issues were alerted to me. That's the best part of this hobby... People willing to help and offer thier advice and experience...

 

[John N]

PS- It's good you found this out now...

 

[John N]

I forgot one other important point to consider, the situation if your overflow drain gets clogged, yet your pump continues to pump H20 to the tank.
This can somewhat easily be remedied with a float switch monitoring a low water level point in your sump or a high water level in the tank (shutting the pump off). If you use the low water level in your sump to shut it off (which helps to assure against pump burnout), be aware that a you may have to rethink your plans if you ever decide to use an auto top-off system.