How to test/unclog bottom Drain

[loki5311]

Hey Guys and Gals,

I Have a 16x 32 pool.
The skimmer has two holes on the bottom with a plate and an adjustable flap that covers one of the holes (closest to pool).
I have a hunch that the bottom drain is not functioning properly.
I have been battling with an green deep end for quite some time.
I have shocked the pool, changed the sand in the sand in the filter and vacuum it daily (including vacuuming to waste)
The pool goes clear after the shock but within a day or two green deep end and clear shallow end.
All tests from pool shop have come back great.
I am convinced that the main drain isn't draining and circulating the water properly.

The pump system is simple --- one line in and one line out : )

Regards,

Jay

 

[Divin Dave]

Hi Jay,
you can tell if your main drain is working by perhaps putting a leaf on it. If it sticks, its working.

In any case though, the main drain is not why your pool is having a problem. It has nothing to do with your pool turning green. The returns alone will circulate teh water sufficiently to chlorinate it.
The reason is because your Chlorine level isn't maintained sufficiently relative to the CYA level.

You need to SLAM the pool. Being a new poster here, I know that is probably a foreign pool term to you. Its about the same as shocking but using liquid chlorine and MAINTAINING shock level FC until testing of the water can prove the algae all gone.

To begin to understand whats happening, TFP recommends to first read the ABS's of pool chemistry.
(you dont need to be a scientist). And no one intends you to get 100% of it right away. But its a start.
http://www.troublefreepool.com/content/123-abc-of-pool-water-chemistry

Also read how to SLAM a pool, which is what you really need to do ASAP.
http://www.troublefreepool.com/content/125-slam-shock-level-and-maintain-shockingl

 

[Richard320]

Clearing up after a shock just means you won one battle -- but you haven't won the war.

Have you read the directions for Shock Level and Maintain? The Maintain is the key. Even if the pool is just cloudy without being green, it usually takes three days. A green swamp can take two weeks or more. So that's one problem - you haven't maintained.

As for the drain.. try sticking the garden hose down the skimmer port that doesn't have suction. If there is a bunch of debris in the line, you may see it come erupting out the main drain. If you have a drain king inflatable bladder, that would work even better.

If your diverter looks like a flying saucer, closing the flap on the bottom completely will put all the suction to the main drain. If the pump maintains pressure and there's flow out the returns, the main drain is flowing. Even working perfectly, there's never a huge amount of suction there.

Concentrate on killing the algae for keeps. Scrub out behind lights, beneath steps and ladder rungs, anywhere it could be lurking, and keep the FC level up to shock level as consistently as possible and you should be rid of the green for keeps.

 

[loki5311]

Thanks fellas!
I will try everything you mentioned!

I will keep you posted.

Regards,

Jay