Help Quiet Down My Overflow!

[18oreefer]

Note. typing fopa.

Wes, You can drain the box faster than you can fill it. When the box drains faster than it can fill it brings the level down to the point at which it sucks air. When air is being sucked in it slows the rate of drain giving the flow into the box a chance to catch up. Once the box submerges the pipe again it will drain all water and no air making it drain at a faster rate again. If you have a pump to closely match the drain then you wont have to restrict the drain much at all. My drain passed a full size Starry Blenny and is quiet. Did you try the experiment i suggested?

 

[Wes]

again it is impossible for this to happen with a drain open to atmosphere. The water falls down the drain only at the rate it is pumped into the overflow box. Think of it as a straight piece of PVC the water level stays at the top of the pipe. As you pump water into the box it falls down the drain.

 

[18oreefer]

did you even read what i wrote. For a brief period when the pipe is not slurping air it will drain faster than the box can fill UNTIL The level falls low enough for it to slurp air. NOW it is draining slower than it is being filled giving the level a chance to catch up...repete. This action will keep the level in roughly the same area, but ultimately the drain is draining too fast.

 

[Keith P]

For a brief period when the pipe is not slurping air it will drain faster than the box can fill UNTIL The level falls low enough for it to slurp air. NOW it is draining slower than it is being filled giving the level a chance to catch up...repete. This action will keep the level in roughly the same area, but ultimately the drain is draining too fast.

Mine doesn't surge, it just keeps sipping air. I probably need to tune the amount of air. The problem is that I am constantly adjust my tank's flow...

 

[motortrendz]

hey keith how did u make out?? im doing my drains today and not sure which way im going yet.. made 2 different designs but not sure which will work better.. i posted on my tank thread

 

[18oreefer]

Keith, that means there is a lot of low out of the box and not nearly as much in it.

 

[motortrendz]

guys, quick question.. how muvh lower than the drain slots in the overflow box should the main drain be?? and i have it with a tee the top is capped with a 1/4 valve for an air line..good bad? i figure id be able to fine tune the air being sucked in and the flow rate with a ball valve below the drain...WILL IT WORK? or am i over thinking things??

 

[Keith P]

Keith, that means there is a lot of low out of the box and not nearly as much in it.

But it's MUCH quieter with the flow greatly restricted on the return side. Keep in mind I'm starting with a 1200 GPH pump.

 

[batt600]

That overflow box is only rated at 750gph thats it. That pump it to much for the overflow thats why you are getting that gruggling noise, had the same problem and nothing worked upgraded my overflow to a 1300gph overflow box and drilled a sec drain hole and is very quit now.

 

[18oreefer]

Keith, im speaking from experience of what works for me. and if i restrict the drain out of the box to the sump then my box gets quieter. You must have something different going on, so I throw up my hands and conceit that my advice is useless. Good luck sir.

 

[Keith P]

Keith, im speaking from experience of what works for me. and if i restrict the drain out of the box to the sump then my box gets quieter.

No one is going to deny that restricting the drain will quiet it. But this practice greatly raises the possibility of a flood. It requires a backup drain which I don't have.

 

[batt600]

Look you are pumping to much water in that 750gph overflow . Throw a mag drive 7 and your noise will be gone. Add some power heads for flow thats it.

 

[motortrendz]

mag 7 minus head height your only gonna be putting out 400gph..just a thought..and do u have 2 overflow boxes or 1?

 

[batt600]

Ok so a mag 9.5 will do forgot about that.

 

[motortrendz]

Ok so a mag 9.5 will do forgot about that.

hey thats why were here!!

 

[Wes]

mag 7 minus head height your only gonna be putting out 400gph..just a thought..and do u have 2 overflow boxes or 1?

400 gph is plenty


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[Wes]

did you even read what i wrote. For a brief period when the pipe is not slurping air it will drain faster than the box can fill UNTIL The level falls low enough for it to slurp air. NOW it is draining slower than it is being filled giving the level a chance to catch up...repete. This action will keep the level in roughly the same area, but ultimately the drain is draining too fast.

This up and down flushing problem is not the box "draining too fast". When the box flushes up and down it's too much flow going into the box. The drain can't keep up. Instead of reducing the return flow like you should have, you increased the flow and restricted the drain. You essentially turned a drain into a syphon. This increases the chance of a flood and is bad advice.

The drain is only designed for a max of 750 gph like mentioned above.


Sent from my iPhone using Reefs

 

[batt600]

+1 Wes Thats what i been tying to say to much flow...

 

[18oreefer]

I run 3600 gph in 2 boxes and my over flows are quieter then church mice.

 

[adamt]

on my last tank with an overflow I lined the inside of the overflow box with blue filter pad and it ended up growing a nice mat of hair algae on it. It was quiet as a church mouse and that tank never saw a red lamote test result EVER (no nitrates )