Help with Increasing Flow through Overflow Compartment

[Buzz1329]

Flow capacity on my four year old 75 has been gradually reducing over past year. I have cleaned overflow compartment several times and covered overflow compartment with black plastic to reduce algae growth and that seems to have helped. But I’m still looking at max of 300 gph flow through sump. So here’s what I’m planning to do:

Install closed ball valve on bottom of drain line in sump

Scrub overflow compartment with brush and then siphon out compartment.

Fill overflow compartment with vinegar so that drain and tubing leading to sump are submersed in vinegar

Let sit for day

Scrub the hell out of overflow compartment and then siphon out compartment.

Fill with RO/DI water.

Scrub the hell out of overflow compartment and then siphon out compartment.

Open ball valve and drain remaining muck from overflow into bucket.

Close ball valve, fill compartment with SW and then scrub/siphon/drain remaining muck.

Remove ball valve and place filter sock on drain

Fill overflow compartment with SW and resume normal operations

Try increasing flow on RP.

Any suggestions/alternatives are welcome.

Thanks,

Mike

[Meshmez]

have you replaced the plumbing?

[jacksonpt]

Any chance the output from your pump has dropped, and that's the problem... not the overflow/plumbing?

[BrettDS]

I have a hard time imagining how a dirty overflow compartment would reduce flow at all. I think the bottle necks would either be in the plumbing or possibly in the teeth. If you increase the water flow to your tank and water is still falling into the overflow but the water level in the tank is getting dangerously high, then it would seem like the teeth are the issue and you might want to get a brush and scrub them out to make sure there is no algae or anything restricting the flow.

If the level in the overflow compartment rises with the tank water and gets dangerously high, then the restriction is likely in the plumbing. You may be able to try to clean out the plumbing somehow, but just replacing it may be the best option.

And like someone else said earlier, if the issue is just that you're seeing reduced turnover then it may be an issue with an old or dirty return pump. The overall turnover rate is controlled by the return pump. The symptom of an undersized (or artificially restricted) overflow would be the water level in the tank getting dangerously high and/or overflowing