120 tank options

intenseimage

Active member
We are getting a new 120rr soon and have a few options to consider in regards to overflows.

A single corner
Dual Corners
Dual Megaflows

What would be the best choice to go with?

I believe the single corner will be "worst" in terms of skimming ability and with only a single drain (not doing an over the back manifold for return) will limit turnover to our basement sump.

The dual overflow options will be equal in drain and return rates but each have their own drawbacks to aquascape and flow.

Opinions?
 
We are getting a new 120rr soon and have a few options to consider in regards to overflows.

A single corner
Dual Corners
Dual Megaflows

What would be the best choice to go with?

I believe the single corner will be "worst" in terms of skimming ability and with only a single drain (not doing an over the back manifold for return) will limit turnover to our basement sump.

The dual overflow options will be equal in drain and return rates but each have their own drawbacks to aquascape and flow.

Opinions?

I have a single corner overflow, and I am using it as a herbie setup, with a piped over the top return.

Personally, I think dual corners is the better way to go then a single center one? I just feel its a lot easier to scape around when you have that added depth front-and-center, as opposed to losing the back few inches of the tank in the most prime real-estate area of the tank (the center).

But if you are starting fresh and don't already have a tank, and are worried about skimming, maybe look into getting an external overflow installed along the entire top/back of the tank. It doesn't take up any room in the tank, and gives you a lot of freedom with the plumbing in the back. Thats if you have a custom tank build, I'm not sure if you were buying a brand-made one ready to go out of the box.
 
Personally, I think dual corners is the better way to go then a single center one? I just feel its a lot easier to scape around when you have that added depth front-and-center, as opposed to losing the back few inches of the tank in the most prime real-estate area of the tank (the center).

But if you are starting fresh and don't already have a tank, and are worried about skimming, maybe look into getting an external overflow installed along the entire top/back of the tank. It doesn't take up any room in the tank, and gives you a lot of freedom with the plumbing in the back. Thats if you have a custom tank build, I'm not sure if you were buying a brand-made one ready to go out of the box.

It will be an off the shelf tank which is why the Dual offset-center Megaflow or Dual Corners are really the only options. The tank is viewable from the right side so also taking into consideration having the overflow blocking some of that viewing panel as well.

Its a tough choice
 
It will be an off the shelf tank which is why the Dual offset-center Megaflow or Dual Corners are really the only options. The tank is viewable from the right side so also taking into consideration having the overflow blocking some of that viewing panel as well.

Its a tough choice

If its viewable from just one side, you may be alright. I have my 75 gallon single corner overflow with the back completely painted black, as well as the side of the overflow. Even though the overflow HAPPENS to be on the side of the tank thats visible to the room (its in a corner), it doesn't really inhibit looking at it from the side.

However, I can totally see wanting to go with the center megaflow if thats the case.
 
The megaflows make aquascaping really difficult, as mentioned. That is the worst choice of the three.

Of these three choices, I would get the single corner overflow in the left corner, away from the viewing side. I would go against what you said, and make it a Herbie. A single drain won't be able to handle much flow without noise, unless the hole for the drain is large.

Why not go over the back with the return?
 
The megaflows make aquascaping really difficult, as mentioned. That is the worst choice of the three.

Of these three choices, I would get the single corner overflow in the left corner, away from the viewing side. I would go against what you said, and make it a Herbie. A single drain won't be able to handle much flow without noise, unless the hole for the drain is large.

Why not go over the back with the return?
This tank is replacing a 75 and there is a cutout in the carpeted area where the tank goes that has flooring underneath. With the additional front to back dimension of the 120 we won't have room for the plumbing in the rear

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Another thing to consider ... Any quality differences between Deep Blue (corners) vs I believe Aqueon (megaflows)

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I got a non-RR 120 and drilled the back glass and used a shadow overflow from synergy. It looks great and doesn't take up any ground real estate.
 
Since you're coming out 6 inches, I would come out an extra inch for the plumbing if you can.

If you can't, then I would still do the single corner overflow. Get the biggest holes drilled that you can (1.5" or bigger). Then don't expect to push more than a few hundred gph through the sump. Which is fine, since turnover through the sump doesn't need to be a lot, and most flow in the display should come from powerheads.
 
Since you're coming out 6 inches, I would come out an extra inch for the plumbing if you can.

If you can't, then I would still do the single corner overflow. Get the biggest holes drilled that you can (1.5" or bigger). Then don't expect to push more than a few hundred gph through the sump. Which is fine, since turnover through the sump doesn't need to be a lot, and most flow in the display should come from powerheads.

Yea definitely cant come out that inch - unfortunately just not possible. Drilling the existing hole in the overflow could be a possibility I suppose ...
 
You'll have to see how big of a hole you can order the tank with. Once you buy the tank, the bottom panel will most likely be tempered, and you can't modify it at that point.
 
You'll have to see how big of a hole you can order the tank with. Once you buy the tank, the bottom panel will most likely be tempered, and you can't modify it at that point.
Noted ... I'll see if I can stop by the shop tonight to verify options

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I got a non-RR 120 and drilled the back glass and used a shadow overflow from synergy. It looks great and doesn't take up any ground real estate.

Glass-HolesDOTcom also sells complete kits to drill and install overflows. I put one on a 125 and was very pleased...
 
...The tank is viewable from the right side...

If it has to be through the bottom, and the one side is also open how about one center overflow? surface area should be close to two corners and still be out of the way enough to not obstruct the view.
The collective "they" used to make them that way. Perhaps "they" still do?

Mega anything really sounds like a disappointment.

HTH
 
This may not be the actual answer you're looking for, but I have a 120g 6' with dual corner overflows and I have the left side overflow closed off and have for the past year and a half. Haven't had any issues.
 
So it looks like with a little creativity we CAN in fact do with a single corner overflow (that will luckily be on the non-viewing side too and do a manifold return over the back!
 
Wooohooo! You will be much happier with it that way. More flow + much less noise.

Let us know if you have any questions with the plumbing.
 
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