Need Help with Water Level Fluctuating

[Salty Carlo]

Water in my sump in the return section keeps fluctuating and my overflow does as well at the same time. Water gets sucked in my over flow and then fills, when it hits just over my durso stand pipe it flushes down to the sump and then fills again. I can't seem to figure out whats going on and its making a mess under the tank. Any Ideas.

 

[theMeat]

Your at the max of what standpipe can do. The top of standpipe gets covered with water, which starts a full siphon, then water goes down faster till it sucks air , and repeats. Must sound like a toilet flushing over and over.
Lower gph on return pump.

 

[Salty Carlo]

It does sound a lot like a toilet flushing. I will try to tune down the return pump. It's just strange because I haven't touched my return pump and this only started a few days ago.

 

[Dom]

It does sound a lot like a toilet flushing. I will try to tune down the return pump. It's just strange because I haven't touched my return pump and this only started a few days ago.

I feel that if this is a new development, an not something that was going on when you first set up the tank, something has changed. Have you looked in the drain pipe to see if any critters got in there? I had a similar problem which was caused by snails in my standpipe.

Can anyone say "STRAINER"?

 

[theMeat]

That is weird, maybe some algae growth or some crud in drain plumbing