Modular Marine Overflow leaking

[ReefWithCare]

Hi all,

So I leak tested my overflow today and had a massive leak on my modular Marine overflow. My kit only came with 2 gaskets and I can see that Synergy has 4 gaskets on their kits.

For any MM overflow owners how many gaskets did you get?

I fixed the leak when I placed the nut before the overflow for now - but I don’t think that’s how it’s supposed to work. I’m trying to figure this out as I may need to purchase a pair of bulkheads just to get the gaskets [emoji37]

I’m referencing Syngery’s design that shows 4 gaskets

From what I'm seeing from MM sites it only shows 2 gaskets. This doesn't make sense >_<:

This two part overflow box system also comes with three lids, a drilling template, a 2.375" glass hole saw, two 1.5" bulkheads (with nuts), two 1.5" bulkhead gaskets (to go between tank and exterior plumbing box), three 1" bulkheads, and installation instructions.

 

[roberthu526]

I got two as well. Where did you put your gaskets? In the tank or outside?

 

[ReefWithCare]

I got two as well. Where did you put your gaskets? In the tank or outside?

I originally put them inside the tank and it leaked like crazy. Then tried outside the tank and it leaked very slightly (weird).

It seems like there should be 4 gaskets.

The leak dumps into the overflow and a tiny bit down the tank [emoji29]

 

[Fin]

I think that may be my former post that you quoted above. I would get a couple more gaskets. This "seems" to be a recurrent issue with these overflows. I don't have one, so I don't know, but I sure see posts about this sort of problem more often than one should.

 

[samnaz]

Brs sells replacement abs bulkhead gaskets BUT according to Modular Marine you really only need one. You only need a gasket between the outside of the tank and the external box with this new-ish design.

 

[ca1ore]

Right, the only CRITICAL place for a gasket is between the tank and external box. So, if your overflow has two bulkheads that connect the internal skim box to the external plumbing box then the two gaskets go on the bulkhead stubs where they protrude out of the back of the tank.

 

[ReefWithCare]

I think that may be my former post that you quoted above. I would get a couple more gaskets. This "seems" to be a recurrent issue with these overflows. I don't have one, so I don't know, but I sure see posts about this sort of problem more often than one should.

It’s driving me insane. It’s the only thing that leaks! I’m getting 2 more gaskets. This design doesn’t make sense.

 

[Fin]

It’s driving me insane. It’s the only thing that leaks! I’m getting 2 more gaskets. This design doesn’t make sense.

I have a Reef Savvy Ghost and a Synergy Reef Overflow. Between Felix and Rick, they came up with this type of overflow to begin with. Both of them have two gaskets on each bulkhead.

 

[ReefWithCare]

I have a Reef Savvy Ghost and a Synergy Reef Overflow. Between Felix and Rick, they came up with this type of overflow to begin with. Both of them have two gaskets on each bulkhead.

Both gaskets are the same right? Like it’s the normal bulkhead gasket? One isn’t thicker or bigger than the other?

 

[Fin]

Both gaskets are the same right? Like it’s the normal bulkhead gasket? One isn’t thicker or bigger than the other?

All the same.

 

[JoshH]

If it's leaking ever so slightly now it could be too much weight on the overflow box that's causing it to pinch the gaskets. If your plumbing isn't supported some way, try supporting it to see if that stops the leak. Not really an issue with 4 gaskets but could be a problem with just the two.

 

[ReefWithCare]

I just ordered 2 more bulkheads since I can't get gaskets separately. Hopefully it works. I'll try the support as well, but I feel it's the lack of not having a pair of gaskets inside the tank.

 

[Fin]

To me, if you only use the one gasket, it is like installing a bulkhead with the flange side against the glass on the inside of the tank, with the gasket on the outside. That would be the incorrect way to install a bulkhead. To me, it is the same thing here.

 

[samnaz]

Why not get the gaskets from brs?

 

[ReefWithCare]

Why not get the gaskets from brs?

BRS takes way too long. I’ve had serious shipping issues with them. I even pay extra for 3 day shipping and it take 5 days. I would would do local if I could. Bigger stuff no problem. But this is a little time sensitive since I have the tank filled up.

 

[samnaz]

BRS takes way too long. I’ve had serious shipping issues with them. I even pay extra for 3 day shipping and it take 5 days. I would would do local if I could. Bigger stuff no problem. But this is a little time sensitive since I have the tank filled up.

That’s odd, my last few orders arrived in two days flat and I didn’t even upgrade shipping.

 

[ReefWithCare]

That’s odd, my last few orders arrived in two days flat and I didn’t even upgrade shipping.

Ya unfortunately its been my experience with them. MD I haven’t had an issue but their warehouse is closer to me. If it’s time sensitive I won’t get from them or try local or overpay and get it on Amazon. Otherwise they are fine.

 

[ca1ore]

To me, if you only use the one gasket, it is like installing a bulkhead with the flange side against the glass on the inside of the tank, with the gasket on the outside. That would be the incorrect way to install a bulkhead. To me, it is the same thing here.

It's actually not. I've got a MM installed just fine with the single gasket between the back of the tank and the external box. With a single gasket, water can seep between the tank and the external box; but installed properly it should not leak down the back. The OP would need to describe his situation in a bit more detail. Perhaps there is a chip in the ground hole that the gasket does not fully overlap, or perhaps the gasket is on a painted back rather than clean glass. Both of those things can cause a slow leak.

 

[ReefWithCare]

It's actually not. I've got a MM installed just fine with the single gasket between the back of the tank and the external box. With a single gasket, water can seep between the tank and the external box; but installed properly it should not leak down the back. The OP would need to describe his situation in a bit more detail. Perhaps there is a chip in the ground hole that the gasket does not fully overlap, or perhaps the gasket is on a painted back rather than clean glass. Both of those things can cause a slow leak.

The tank is painted in the back. That could be why it’s leaking because all the other bulkheads do not leak with the gasket on the inside of the tank.

The Hole was VERY clean. Way better than another hole I have for my return that was pretty bad yet doesn’t leak [emoji848]

This hole here is my return - it’s a pretty crappy cut from here and the inside - but no leak. Gasket is on the inside of tank [emoji848].

 

[Caravanshaka]

It's actually not. I've got a MM installed just fine with the single gasket between the back of the tank and the external box. With a single gasket, water can seep between the tank and the external box; but installed properly it should not leak down the back. The OP would need to describe his situation in a bit more detail. Perhaps there is a chip in the ground hole that the gasket does not fully overlap, or perhaps the gasket is on a painted back rather than clean glass. Both of those things can cause a slow leak.

This is how it is designed. Any water getting through the bulkhead will simply make it back to the overflow box since the box is sealed to the tank.

That being said, I think it can and should be improved. The issue with this design is that water will slowly trickle through to the overflow box until the water level in the DT gets below the bottom of the drilled holes....for some people that could be a disaster if it is left not running for a day or more due to a power outage. I would much rather know that the bulkhead is sealed at the tank.

When I install mine this week I am going to put a sheet gasket between the tank and the overflow box, and use the bulkhead gaskets inside the tank. To me, this will give a much better seal, as it will support the overflow box at all points instead of letting it hang a little with just a round gasket between it and the tank. For $9 on amazon, I got a 12"x20" sheet of 1/16" rubber gasket material, and will simply cut it to the size of the overflow box, and cut out the circles for the bulkheads to slide through.