Water level up and down

We just hooked up the refugium today. The water level where the pump goes, constantly goes up and down. We've adjusted the air intake valve. But, it's still doing it. Is this normal ?

 

What type of overflow do you have? Does the water level go up and down in it too? Do you have a sump as well? How is the refugium plumbed?

 

if you can describe you system better or take a picture it may help, as i dont understand y you have a air intake valve on a fuge.

 

I'm no expert but something similar happened to me in my drilled overflow, the water just constantly swelled and drained, i didnt know what to do so i just left it and it eventually reached an equillibrium i guess.

 

It's possible your pump is too strong for the overflow.

if you have a 300gph overflow, and your pump is moving 400gph then your overflow and sump will kind of surge.

I had the same problem, fixed it by putting a ball valve inline with the return pump and throttleing it back about 20%. No more surging.

 

...yeah I'm new to this as well, but why would a fuge have an air intake valve? The only variable air intake I have in my system is on the protein skimmer.

the Durso standpipe in the overflow (I have a drilled tank) has an air hole on it, but it's pretty much set at one flow rate.

 

I have a megaflow on it. That is where the air intake valve is. If I move it up or down, it makes the water on the pump side, that returns the water back to the tank, go up and down. Actually, the air intake piece was missing from the box. I put an elbow on it and drilled a hole in it. It made this gurgling sound, so I put a piece of tubing in it. The gurgling sound isn't there anymore. But, I was concerned about the water level not being stable.

 

Couple things....

If you move your stand pipe up and down it will (and should) directly correlate to the water level in the sump. You're lowering the water level n the overflow, that has to go somewhere. That's normal.

Any changes in water level will show up in the sump. Evaporation loss, adding water, and moving the standpipe all affect sump levels.

I'm curious what standpipe kit you got... pics?

At any rate, the reason I've seen surging in the over flow and sump is because my return pump was pushing more water than the overflow could make up for. I backed the flow off on the pump and it's stable now.

 

It's a 90 gallon aquarium, I bought a 900 gph pump.

 

How many GPH does your pump put out at say 4 1/2 foot of head (there should be a chart on the box). If it's greater than 600 GPH, then your pump is overwhelming the overflow and that's why you're getting the surging.