Help with Overflow

[milkshake]

I acquired an overflow box from a friend here recently and hooked it up last night. I am having a problem with water level being to high and not any skim(from what I see). I am running a Iwaki MD-20RXLT for the returns. There is a 1 inch drain on the overflow. All drains and returns are pvc with ball valves for each.
Could this simply be that the setup will not handle the flow? It is 4'6" from floor to top of tank. I have (4) 90 degree elbows, (1) "T",
and (2) 45 degree couplings that are all tied into the return line.
Here are some pic's...
http://reefcentral.com/gallery/data/586/110068DSC00776.jpg
http://reefcentral.com/gallery/data/500/110068DSC00778.jpg
http://reefcentral.com/gallery/data/500/110068DSC00779.jpg

I need all the help with this folks....I dont want the wife giving "CPR" to me due to a spill. :bounce1:
:uzi:husband

 

[sjm817]

Flow Rate @ 4` Head: 540 GPH

It looks like the overflow cant handle that much.

 

[milkshake]

yeah...it could be that all I need to do is remove some water from the tank and slide the skim box down?

 

[sjm817]

I don't think so, it looks like the water rises up pretty high which means more flow than the overflow can handle. Can you bypass some of the flow from the return pump?

 

[milkshake]

I'm glad I decided to just put a dab of acrylic glue where the drain line slides into a coupling. This way I can just twist it out without having to cut any pipe off. sjm817 I appreciate the help. I was kinda thinking the same thing. Especially when I noticed that water is having to stay a 1/4 inch above the skim box.

 

[Scottdl99]

try a ball valve on the return line from the pump.

 

[milkshake]

I already have 2 ball valves. One one each return pipe. I have tried turning them down some to restrict the flow into the tank and that's when the water level drops and the overflow box starts sucking air. For everything to run smoothly, the water level has to be about a 1/4 inch above the skim box. weird??

 

[sjm817]

No, not weird. The level in the inside of the skimmer box should be below the bottom of the teeth for it to work properly. Turn back the flow until it is. Yes, the drain side of the box will draw air. This is normal. You can quiet it with a variety of methods. You can insert a piece of airline, or use a standpipe such as a Stockman.

 

[manderx]

it should siphon faster than it is. that's a pretty big difference in waterlevels between the tank and the overflow box. maybe your u-tube is smaller than i am used to. so a bigger u-tube, or maybe a second one will fix you.

*never* use a ballvalve on the drain line. it's a flood waiting to happen.

 

[milkshake]

manderx...why is ball valves a bad idea in the drain line? The way I have my sump set up I have to have a line going to the ASM skimmer, which is at the other end of the sump. The other line of course is at the other end with a bubble trap and then fuge after that. How would you control the flow? My sump is drilled midways (on the side) for the external pump.

 

[sjm817]

Can you post a diagram of the setup?

 

[manderx]

because a snail or hermit *will* take a magic ride sooner or later and get stuck on the ball valve, partially blocking it. as long as you don't also have a valve on the line that goes straight to the sump you should be fine.

too many people use a valve on a simple drain (not split to skimmer) to raise the water level in the outside overflow box a little so it doesn't suck air.

 

[milkshake]

Give me a few minutes and I'll take a picture of it...brb

 

[milkshake]

Still trying to get everything set up...so nevermind the mess.

 

[milkshake]

Don't know what I did wrong there on posting the pic's but the links still made it.

 

[wjhuie]

why are the ball valves partially closed on the drain lines.

 

[wjhuie]

is it sucking air in the pipe in the outside box

 

[milkshake]

no...not right now it's not. I have the level set in the tank a little high so that it will not make the sucking sound. You have a PM too Walker.

 

[manderx]

what's the point in splitting the drain? i've seen some people split it so they could have raw water split between a skimmer and a fuge, but it doesn't look like the water draining to the left side of the sump hits a fuge before the return pump.

 

[sjm817]

It looks like you could control the drain flow split with just the valve on the left and leave the valve on the right open