20 gal refugium

[SamD]

I have been looking around on R2R but haven’t be able to find an answer. I have a 90 gal reef tank with a sump but it’s not big enough for a refugium. I have an extra 20 gal tank laying around. Is it possible to tie that in to add an extra 20 gal of water and refugium to the tank? I understand how and why a refugium works but can’t figure out how to tie it back into the sump/return pump.

 

[mrlavalamp]

Place the fuge tank higher than your sump and set it up to overflow back into the sump.

If your main return pump is large enough, you can T into that line and use a valve to throttle the water fed to the fuge. If not, you can place a small pump in the sump just for supplying the fuge.

 

[SamD]

Place the fuge tank higher than your sump and set it up to overflow back into the sump.

If your main return pump is large enough, you can T into that line and use a valve to throttle the water fed to the fuge. If not, you can place a small pump in the sump just for supplying the fuge.

The glass is taller than the sump so that should work fine or I can place it on blocks, how do I set it up to overflow back?

 

[mrlavalamp]

If you can drill the 20, I would use a small add on overflow box with the drilled bulkheads. One like this: https://www.marinedepot.com/marine-depot-elite-overflow-box-w-holesaw-drill-bit-small

If you can't or dont want to drill it, then the HOB overflows aren't too bad. https://www.marinedepot.com/marine-depot-overflow-box-of-300

Main issue with the hob overflows is they can loose siphon and then you risk a flood (the pump filling the fuge will just keep filling and none of the water will go back to the sump). This is why the drilled overflow boxes would be my first recommendation. If you go the HOB route, I would definitely look into the autoaqua smart level sensor safety switch : https://www.bulkreefsupply.com/smart-level-security-autoaqua.html

 

[LuisPerez711]

The glass is taller than the sump so that should work fine or I can place it on blocks, how do I set it up to overflow back?

I did what you are planning to do. I could only fit a 10 gallon but I placed it at the end of my sump. I elevated the refugium above the sump walls and then used a HOB drain from Marine Depot to have the water overflow back into the sump. Simple and straightforward.

 

[LuisPerez711]

I have never had a siphon issue. Had a few brown outs and the overflow kept siphon every time.

The issue is when you do not run enough flow through the overflow box. Air bubbles start to accumulate at the top of the siphon tube and that can cause issues. Just run enough flow and you should be fine.

Extra precaution would be to add a float switch or that sensor mentioned above.

Edit: Also, try to cover the overflow tube so that algae doesnt grow inside. This happened to me within the first month and air started to get trapped in between the algae. I now have a cover and no issues with algae. Hope this helps.

 

[FishGeist]

Here is a pro tip if you decide the HOB route. Cover the U pipe/Top of the overflow with a modified rubber floor mat to shade the pipe from ambient fuge light. It will stay cleaner longer, like 3 or 4 months, IME, YMMV.

 

[LuisPerez711]

Here is a pro tip if you decide the HOB route. Cover the U pipe/Top of the overflow with a modified rubber floor mat to shade the pipe from ambient fuge light. It will stay cleaner longer, like 3 or 4 months, IME, YMMV.

Haha I had just remembered this so I edited my post. Come to find out you had posted the same thing lol

 

[SamD]

I did what you are planning to do. I could only fit a 10 gallon but I placed it at the end of my sump. I elevated the refugium above the sump walls and then used a HOB drain from Marine Depot to have the water overflow back into the sump. Simple and straightforward.

Oh I see now, thank you!

 

[SamD]

Here is a pro tip if you decide the HOB route. Cover the U pipe/Top of the overflow with a modified rubber floor mat to shade the pipe from ambient fuge light. It will stay cleaner longer, like 3 or 4 months, IME, YMMV.

Oh good to know! Thanks!