Quite overflow with one rtn pump but loud with two pumps???

[ReefBeta]

PNW! WA is my home state.

I do have a small hole drilled in the secondary pipe.

I've tried removing the main drain "U" but with no luck. I'm pretty I didn't glue that sucker in there but it's not coming out. I'm thinking when I glued in the under side some of the glue pushed up and cemented the "U" side plumbing. Not too happy about that.

also wondering, are the overflow and return pipe the same size? They look pretty close in size. If they're the same, or even 1" vs 3/4", it's possible that two 3/4" return line in full capacity is over the overflow capacity of a 1". The actual capacity of the overflow pipe is smaller than the same size as return pipe, because return pipe has the return pump to add additional head pressure.

 

[Bodyguard]

also wondering, are the overflow and return pipe the same size? They look pretty close in size. If they're the same, or even 1" vs 3/4", it's possible that two 3/4" return line in full capacity is over the overflow capacity of a 1". The actual capacity of the overflow pipe is smaller than the same size as return pipe, because return pipe has the return pump to add additional head pressure.

The drains are all 1". The return lines from the pumps are 3/4".

 

[Water Dog]

How is this a "lousy" design??? I mimic it from the BRS160 build (except I have two pumps).

The “lousy” design that Ca1ore mentioned and I alluded to is the fact that the external drain box sits lower than the internal weir box. This givs you a narrower window of adjustment when running at higher flow rates to avoid the waterfall sound that you’re experiencing. That lower external box gives the water coming in through the weir a longer distance to fall leading to more noise.

Unfortunately, this is made worse because the pipes in your drain box are glued in. That already narrow room for adjust ment is now not possible without redoing the plumbing in the drain box.

I would suggest buying a new bulkhead and union so you can dismantle the glued in secondary trickle drain. Use that new bulkhead and half the union to retrofit a pressfit (non glued) adjustable solution for the secondary drain. By raising the secondary drain height, you will shorten the “waterfall” thereby reducing the sound. You will be able to tune it to run silent. That glued in secondary trickle drain sitting so low is the root cause of your issues IMO. I don’t think adding a gate valve to it will remedy anything.

This is why I prefer Modular Marine or Exotic Marine Systems overflows as the internal weir box and external drain box are the same height. This dramatically reduces the waterfall effect and gives you more room to tune your system to run silent. For the record, I use a Modular Marine overflow on my system.

 

[Bodyguard]

Thanks Water Dog for the feedback

That does make sense. I had already thought and placed replacement parts in my BRS cart to redo the secondary drain but was hesitant to break the leak proof seal. If raising the secondary is the only way I can get rid of the water fall sound, I will have to do it. Otherwise I will go nuts hearing it.

When gluing the PCV, how long do I have to wait before I run my water through it? I'm worried the pvc glue introduce toxic chemicals. It's only to pieces I have to glue to that should minimize chemical introduction.

 

[Water Dog]

Measure and cut the PVC and pre glue everything together and leave it off to the side for a day or two, a minimum of 24 hours. Once cured swap it out. It should be a pretty modular plug n play replacement because of the union connection.

 

[ca1ore]

How is this a "lousy" design??? I mimic it from the BRS160 build (except I have two pumps).

There are countless threads on this and the other overflow boxes that mount the external box lower than the internal skim box. Makes it very difficult to keep things quiet as you increase flow. That constitutes a lousy design in my book. The better ones have both boxes at the same height.

 

[Buffalou]

How does this cause a issue? I'm not sure I understand why it would have a negative effect. The Durso drain does sit higher than the main drain.

Sorry for delay in answer, it just looks like it would not give you much water level to adjust with. I start my pumps at whatever level of pressure I desire, for me it's half way for both my vario -6. I ensure my two return line valves are fully open. I look in my sump and visually check for water returning from main drain. Once I have initiated the full flow I start to close down on main drain gate valve until I get flow from the durso line return to sump I then close down on durso gate valve until it's almost above durso elbow. I struggled with the same issue for weeks until I installed second gate valve and drilled hole in top of durso. I experienced to much water returning to my sump without gate valve on durso to maintain the level I wanted in my tank without the constant cavitation. I might have just got lucky, as I'm not a plumbing genius when it comes to higher, lower overflow boxes etc. I dealt with a lot of pump fluid cavitation and supply issues in Navy, (Retired Catapult and Arresting gear maintenance officer, I might add greatest and exciting job in world running around flight deck launching and recovering jets, I digress sorry! ) but this worked for me good luck and happy reefing.

 

[Bodyguard]

There are countless threads on this and the other overflow boxes that mount the external box lower than the internal skim box. Makes it very difficult to keep things quiet as you increase flow. That constitutes a lousy design in my book. The better ones have both boxes at the same height.

Yeah I'm discovering that now. Whenever I go to a bigger tank I will be going to a different overflow box that Water Dog suggested. Lesson learned as we are always learning from mistakes in this hobby but do our best to avoid them.

As Water Dog posted, I'm going to remove the secondary drain and replace with it with a high drain to reduce the fall of water into the weir to the overflow box.

 

[Bodyguard]

Sorry for delay in answer, it just looks like it would not give you much water level to adjust with. I start my pumps at whatever level of pressure I desire, for me it's half way for both my vario -6. I ensure my two return line valves are fully open. I look in my sump and visually check for water returning from main drain. Once I have initiated the full flow I start to close down on main drain gate valve until I get flow from the durso line return to sump I then close down on durso gate valve until it's almost above durso elbow. I struggled with the same issue for weeks until I installed second gate valve and drilled hole in top of durso. I experienced to much water returning to my sump without gate valve on durso to maintain the level I wanted in my tank without the constant cavitation. I might have just got lucky, as I'm not a plumbing genius when it comes to higher, lower overflow boxes etc. I dealt with a lot of pump fluid cavitation and supply issues in Navy, (Retired Catapult and Arresting gear maintenance officer, I might add greatest and exciting job in world running around flight deck launching and recovering jets, I digress sorry! ) but this worked for me good luck and happy reefing.

I'm a fellow Vet myself.

Didn't know adding a second pump would be a headache. I love the idea of having two pumps for redundancy but it is causing some re-work. But learning new things to consider for the next tank.

 

[Bodyguard]

Measure and cut the PVC and pre glue everything together and leave it off to the side for a day or two, a minimum of 24 hours. Once cured swap it out. It should be a pretty modular plug n play replacement because of the union connection.

Unfortunately one of the ends I can't preassembly/glue. Have to use just enough glue to keep minimal glue from going into the wet side and let it fry for a couple hours.

 

[Water Dog]

While you’re at it, you may want to raise the emergency open channel as well. In taking a look at the picture of your overflow box plumbing, you definitely have the space. If you don’t want to dismantle it, then perhaps use a Dremel tool to trim down a coupler fitting and press fit it onto the existing red emergency tube to raise the height.

Also, when you redo the secondary trickle line in the box, don’t forget to have a breather hole drilled atop the U-fitting comprised of the 2 elbows. Have a few pipes cut of varying lengths so you can play with the secondary drain height... Remember, do not glue anything on the secondary drain inside the box... press fit only!

 

[Bodyguard]

Update to all on this thread.

Finally got the plumbing parts to do the modification. I raised the secondary drain as high as I could that would minimize the water fall drop from the weir to the overflow box but also giving the emergency drain room. There is still some water fall noise. Not as bad as before but definitely noticeable and not nearly as quite when I just run a single return pump. Still have that "whistling" of the water flowing through the weir slices with both pumps running too. I believe now that this ESHOPPS-L overflow box is really only good for one return pump if you want no noise. Really does work great but not with two return pump.

Not sure what I'm going to do now to eliminate the noise all together. Don't think its possible to move to a different overflow but definitely will be using something else that can handle two pumps running and remain quite when I move to a new tank.

Thank you everyone for the feedback. If anyone has anything else in mind that may work to eliminate the noise I'd appreciate the input.

 

[Water Dog]

If you get to the point where you‘re thinking of ditching the Eshopps altogether, Exotic Marine Systems has been known to retrofit his ghost style overflow boxes with other manufacturers’ hole patterns to alleviate the noise issues inherent with the drop down external box style overflows. I’m sorry that the suggestion of raising the standpipe heights didn't fully solve the problem.

 

[ca1ore]

Yeah I'm discovering that now. Whenever I go to a bigger tank I will be going to a different overflow box that Water Dog suggested. Lesson learned as we are always learning from mistakes in this hobby but do our best to avoid them.

It’s unfortunate that so many of the ghost style overflows appear to have copied a flawed design. I’m using the eshopps M on my QT tank, but it’s in the basement sump room so who cares if it makes noise LOL. Display in the family room uses a Modular Marine unit. Not silent, certainly, but quiet enough. Nice thing about the MM is that the teeth slots are beveled which helps to reduce any mechanical water noise.

 

[Bodyguard]

If you get to the point where you‘re thinking of ditching the Eshopps altogether, Exotic Marine Systems has been known to retrofit his ghost style overflow boxes with other manufacturers’ hole patterns to alleviate the noise issues inherent with the drop down external box style overflows. I’m sorry that the suggestion of raising the standpipe heights didn't fully solve the problem.

Raising the stand pipe definitely helped. Thinking of putting a thin mesh screen behind the weir teeth to see if that stops the noise