AGA 90 w/overflow to basement - quieting down

[luckycat]

I have a 90g aga w/built-in overflow, and their overflow kit that basically includes a durso-type overflow. The only difference I see between the aga kit and the durso standpipe is that the aga has some holes just under the "t".

Anyway, my overflow goes first through about 2' of spa-flex pvc (1 1/4"), which then goes to rigid PVC (1 1/2") straight down to the basement (about 9' drop).

The problem I'm having is that I hear a constant flow of what I think is air coming from the aquarium, plus waterflow through the pipes. I tried making the air hold at the top of the standpipe a bit bigger, but honestly don't know if it made a huge difference.

In this scenario would making the hole larger potentially quiet it down?

I'm thinking of wrapping my spa-flex and pvc with some kind of sound absorbant material - has anyone done this and if so what material did you use? I'm thinking that some double-sided insulation might work?

EDIT: More information...seems like most of my noise is coming from the spa-flex and pvc tube going down to the basement. Not sure how I can quiet that down...the standpipe itself is fairly quiet, but I do hear what sounds like air or could be start of a siphon that gets loud for a few seconds before it quiets down.

 

[luckycat]

And more information: I've played around quite a bit with the return; it is some air I'm hearing constantly, and water flowing. I don't have surges (up and down), just constant running water that is very loud.

After reading up some more articles I'm thinking that perhaps my overflow is too small. I have a Mag 18 that is driving up water about 9'. The Head Loss calculator on reefcentral says that I have about 961 gph pumping back up to the tank...and remember I have only a 1" overflow in my AGA 90. I read several articles about this not being big enough for 600 gph or more, but read some other ones that said it woudln't be a problem.

Perhaps that is the problem, I'm trying to push too much water down the 1" overflow...maybe using the 3/4" return in the overflow chamber as a 2nd drawin would remedy the situation?

Any suggestions?

 

[seaham358]

Before you go through the work of running the other line get a ball valve first and cut back the return flow and see if that helps. I would think if you were pushing too much water back to the tank it would overflow if the overflow could not handle it.

 

[ellisz]

Does your water level in the overflow rise and fall? There are other stand pipe designs out there that supposedly work better than the Durso in some situations.

Mine is the same way. I have a Mak4 that is pumping about 770 gph at my head height. I modified my overflow in hopes in would handle more flow.

In the beginning my overflow would surge but that went away. I guess the the newness of the pipes caused this? Seems like the overflow quieted itself down over time but now it is noisy again. Not sure what happened.

I toyed around with modifying my Durso but never got around to it. Might have to look again.

 

[luckycat]

Before you go through the work of running the other line get a ball valve first and cut back the return flow and see if that helps. I would think if you were pushing too much water back to the tank it would overflow if the overflow could not handle it.

Yeah great idea, I have an extra valve I can insert, with some more plumbing work (joy) to try that out..but great experiment.

 

[luckycat]

Does your water level in the overflow rise and fall? There are other stand pipe designs out there that supposedly work better than the Durso in some situations.

Mine is the same way. I have a Mak4 that is pumping about 770 gph at my head height. I modified my overflow in hopes in would handle more flow.

In the beginning my overflow would surge but that went away. I guess the the newness of the pipes caused this? Seems like the overflow quieted itself down over time but now it is noisy again. Not sure what happened.

I toyed around with modifying my Durso but never got around to it. Might have to look again.

I don't get surging (rise/fall)..I did initially but I adjusted the height so there is no more surging. I also drilled a new hole, and opened up the existing hole a bit, thinking that could be the cause for my noise problems...but I don't think it has to do with siphoning. When I force a siphon by blocking the holes it is a very different noise that I hear.

It's a steady level in the overflow, it's just that I hear constant waterfalling sounds going down to the sump. There is some noise coming from the bottom of the tank too where the drain comes out. I wrapped up the pipes there with a blue styrofoam blanket (used for insulation around windows and on sills and stuff) which did help a bit but most of the noise is from the overflow area, specifically the drain pipe.