WB20 Cube 3rd chamber low, 1st chamber high

LagunaGlide · Jul 29, 2021

I have had my WB20 cube set up since december. I have a syncra silent 0.5 for the return pump, and I put the intank media basket in first chamber. I cut up the black filters that came with the tank and put them in the top of the media basket, filter floss in the second, and in the third I use chemipure blu. In the middle chamber I have some rock rubble, heater, and had the ATO set up in there. It was running like this for months with no issues. Performed weekly water changes, and changes filter media at this time as well.

All of a sudden in the past 2 weeks the 3rd chamber has been emptying while the tank level has risen as well as the first chambers water level. It has gotten so bad that the return pump was sucking air in the morning, and the water was touching the lid in the display. I have pulled literally everything from the back of the tank, cleaned it all up, checked for blockages in the baffles (found none), and put it all back in. I ran it for one day and it started again. I pulled the media basket, removed the floss, and ran just the filter, and it happened again after two days. I pulled all filter media except the chemipure and same thing after a few days. I put the factory sent pump back in, and same issue. I can't figure out what is causing this issue. I would also like to note that the pump is blowing microbubbles into the display when the water drops, but is somewhat expected. Though I think it may be sucking air through the hose.

I am really at my wits end with this thing. Any help appreciated.

Saltyreef · Jul 29, 2021

The water level in the return chamber will drop with evaporation.
It should be kept nearly full (as full as possible).

Are you using an ATO? If so that will keep the water level stable in the 3rd chamber and negate you having to add water by hand to keep salinity from rising.

The syncra pump has an adjustable flow rate dial in the front but you said this issue persists with the original pump so in still thinking over here.

Have you just plain removed the baskets yet?

LagunaGlide · Jul 29, 2021

Saltyreef said:
The water level in the return chamber will drop with evaporation.
It should be kept nearly full (as full as possible).

Are you using an ATO? If so that will keep the water level stable in the 3rd chamber and negate you having to add water by hand to keep salinity from rising.

The syncra pump has an adjustable flow rate dial in the front but you said this issue persists with the original pump so in still thinking over here.

Have you just plain removed the baskets yet?

I haven't ran it with the basket completely out, no. I was using an ATO on the third chamber, but I took it off because my wife thought it overfilled the tank during one of these spells. Currently it is running with just the chemipure again, but I don't know how long that will last, and that means no filtration on my tank.

I removed the flow rate dial awhile back and it has been running wide open for months. I can't imagine it has suddenly started pumping more water and the first chamber can't keep up anymore. Also same issue with old pump as you noted.

saltybees · Aug 2, 2021

Take the baskets out and see what the water level does, sounds like there’s some sort of restriction happening between the chambers. Maybe just needs a good cleaning between the weirs etc

BostonReefer300 · Aug 2, 2021

I bet the black sponges in your first chamber are clogged even if they look clean. My daughter's WB20 had a similar issue (although we had the black sponge in the second chamber). We removed the sponge and everything worked fine again.