Plumbing dual overflow tank

[Reefinmike]

Hey all, I’m upgrading one of my tanks from a standard 110 to a marineland rr 120 with two corner overflows, drilled for 2 1” bulkheads each. I would like to plumb it bean animal style for absolute reliability since i will only see this tank once a week. It seems the major drawback is that one overflow will carry 99% of the water while the other one sits stagnant. I wouldn’t rely on the backup durso drain to allow proper circulation so one overflow will be used for the return line and the backup emergency drain.

Option A- drill a hole or two low down on the return line so the box fills and overflows back in the display.

Option B- drill several large holes in the overflow essentially “deleting” the overflow while keeping the bulkheads and lines protected.

Option C- a small circulation pump at the bottom of the overflow aimed at the surface to keep it from getting stagnant.

Option D- send the return line over over the top and use the extra hole to “T” a line from each overflow to the gated full siphon drain

Any other suggestions? Do any of these methods stand out as problematic or considerably more reliable/redundant than the rest?

 

[theMeat]

Could drill another hole on the bottom of one overflow to have primary and secondary drain in one overflow, and have emergency and return in other overflow.
Or don’t drill and have primary on one side, secondary on the other. This would be harder to adjust.
Could also do herbie style in each corner, and run return over top of rim on back, outside overflow box

 

[ReefHog]

This is what I did on my 220 RR

 

[Reefinmike]

@theMeat are you referring to drilling the bottom glass or the bottom side of the plastic overflow box? I’ve drilled a few small tanks for myself but since this is in someone else’s home i’d prefer to release myself of any liability by using a tank as it is off the shelf. I run a herbie on my tanks at home. From my understanding of the bean animal overflow, the secondary should drain a silent dribble like with a herbie. I wouldn’t want to rely on a few ml/min to keep an overflow from getting a little stagnant.

@ReefHog the way you did it will certainly work but i’m need It to run silently. A single herbie can be adjusted so a few drops go down the drain every once in a while but with varying flow in the tank, i see it being too difficult to keep two backup overflows silent.

 

[theMeat]

Yes, have drilled a third hole into rr overflows a few times. Another option for the other overflow is filling it with sand for dsb. Did this on a few tanks. One of which s 200dd 3 years ago. Still going strong.

Could also remove the plastic overflows.silicone on some glass to plug the holes. Cover them with substrate. Then drill the back of tank for ghost overflow

 

[Reefinmike]

Unfortunately drilling glass of any sorts is off the table from a liability standpoint. I’ll do it for tanks in my own home but not somebody else’s. A deep sand bed is a good idea but i’m a bit hesitant on the idea with so little circulation.

I even considered sealing up the teeth of one overflow and using it to hold ~5 gallons of top off water gravity feeding a float in the sump. Good idea until I realized how much of a PIA it’d be to refill every week. This aquarium will be set back into cabinetry making access difficult.

 

[ReefHog]

@ReefHog the way you did it will certainly work but i’m need It to run silently. A single herbie can be adjusted so a few drops go down the drain every once in a while but with varying flow in the tank, i see it being too difficult to keep two backup overflows silent.

It's still a full siphon with a small amount of water trickling down the second drain in each overflow. Mine is as quiet as any single overflow I have seen. It's just two adjustments instead of one to get it set. You set each one individually. If your still concerned, remove the second overflow and seal the two holes with bulkheads and plugs. You'll also get some valuable real estate back. Just make sure the return pump matches the drain.

 

[dugthefish]

I ran dual Herbies with a return over the top in a reef ready 125. Worked good.

 

[rfischer]

I ran dual Herbies with a return over the top in a reef ready 125. Worked good.

Same here on my 120. No issues.

 

[ca1ore]

The only practical way to run a bean from two independent overflows is to connect them with a balancing pipe, which requires drilling the tank which you’ve already said you won’t do. Fortunately it’s unnecessary as dual herbie drains work fine. Do the over-the-back return in black PVC and it’s hardky noticeable.