Overflow box question

[BigWaz]

I have one of these on my 72 bowfront
http://www.marinedepot.com/md_viewItem.asp?idproduct=CR1513
Now and then it doesn't feel like working and the tank gets very high with water and nearly overflows, i save it everytime except one it overflowed from the top of my tank. It has to do with that little hole, i put a cap on the hole that you get from a maxi jet powerhead, it's those little clear caps i don't don't know how else to describe it. I've had this overflow box for a year and half and always have issues now matter how much i turn the amount of water coming back up, do i have it set up wrong?
Thanks!
Anthony

[Andrew]

Have you cleaned it out? Also, what size of a retrun pump do you have?

[BigWaz]

It doesn't appear dirty at all because it has always done it, my return pump is a via aqua. The overflow box just stops the suction, should something else be on that little hole?

[Andrew]

Are you using the airlift pump?

[BigWaz]

i don't know what that is

[Andrew]

http://www.marinedepot.com/md_viewItem.asp?idproduct=KTALP

[BigWaz]

so i put that in the little hole? That does make a lot of sense. That will keep the overflow box also sucking huh
Cool Thanks
Anthony

[Andrew]

<a href=showthread.php?s=&postid=6371396#post6371396 target=_blank>Originally posted</a> by BigWaz
so i put that in the little hole? That does make a lot of sense. That will keep the overflow box also sucking huh
Cool Thanks
Anthony

Not possitive, but when I was looking at those overflows awhile ago I was pretty sure you needed those air lifters to get them started.

[JaMan]

Or attach one end of air line tubing to the hole on the box and the other end to a venturi on a pump or powerhead. Siphon boxes slowly gather air and the venturi will suck the air out; lowering your chance of breaking siphon. The thing is the pump will slowly get dirty and begin to remove less and less air, so the pump must be cleaned often. Same thing with the airlift pump- it will get clogged. I delt with this for years, then bought a tank that was drilled...no worries now!

[BigWaz]

Jaman, i tried that and it seems t be working, i put an airline to the little hole on the overflow box and the little hole on top of my maxijet powerhead. The suction appears to be powerful all the time now, i hope it doesn't make the water level go high anymore, i think that is what the problem was, thanks
Anthony

[JaMan]

Anthony, just keep an eye on the water level in the tank. Once it seems to start creeping up (maybe in a month), it is time to clean the powerhead impeller.

[BigWaz]

cleaning once a month i can handle, thanks again