Thank you pool doc!! Your the best.....

[Lawrosa]

OK I have a valve before the pump.

I have a valve after the cart.

I can throttle from any of them. If I hook up the sand it would be in series with the cart. Cart first then sand. I remove the cartridge to run sand only.

So in this scenerio I would throttle the valve after the cart, but will be before the sand.

And if this is true how will I know I am at 10 gpm without a flow meter?

Next would I add DE to the sand to accomplish this?

What I am thinking is vac to waste and then filter as you describe.

Thanks. ( And why is this happening? )

Mike NJ

[PoolDoc]

I was assuming you only were using one filter at a time. If both are inline, REMOVE the cartridge before beginning this. Check your sand volume if you can, also.

As far as checking flow, can you have someone hold the vac hose TIGHTLY over the return, and run it into a 5 gallon bucket, and then throttle the flow till it takes 30s or more to fill the bucket?

As far as a full explanation of the problem -- we don't have one. I have some theories, which we're trying to test, but no clear evidence yet. But, you're not the only one.

[Lawrosa]

OK.

So I will vac to waste later on this evening on low speed as to not disturb anything right?

Then I will run the sand filter preferred to the cart correct? I will run on low speed and try to achieve 10gpm, right?

Do I add DE to the sand?

Mike NJ

[PoolDoc]

+ No DE.
+ Sand filter at 10 GPM OK -- if vacuuming successful; otherwise, let it re-settle.
+ You may need to vacuum via a SIPHON, rather than via pump.

[Lawrosa]

+ You may need to vacuum via a SIPHON, rather than via pump.

Why?

otherwise, let it re-settle.

I did not see anything settling. Am I supposed too.

+ Sand filter at 10 GPM OK

Would I be better running the cart and the sand toghther in series on low speed? The cart is first then the sand. The cart will slow the gpm by time it reaches the sand.

I can guess that low speed on my pump runs at about 10 gpm. ( I will pull the return hose tomorrow and fill a 5 gal bucket and time it. ).

Is this mustard algae? I would like to know what you think it is so I can also research additional info.

Mike NJ

[PoolDoc]

+ Not mustard algae; mustard algae leaves yellow brown areas on pool surfaces.
+ If the algae is NOT settling, after 48 hours with no circulation, it's not going to settle. So much for that.
+ I'd recommend running only ONE filter with the pump on low, 24/7. If you're sure the cartridge is in good condition, use it, not the sand filter.

-- Maintain consistent chlorine levels
-- Do NOT turn the pump on high!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!

What I suspect is happening to a lot of people with sand filters on AG pools, is that forcing the algae through the sand filter fractures the particles, and makes them hard to filter by any method.

What I know is that BOTH of your filters will perform much better on low speed, than on high. Once the pool is clear, you can probably run the cartridge filter on high, if you want to do so. But you should NEVER run the sand filter on high, especially during clean up.

[Lawrosa]

OK Ben.

Last question.

Since I have no CC now do I still keep the CL levels at shock until the pool cleans 100%? Or can I lower the CL to say 3ppm now and its just a filtering issue.

It was down to a 7 today and I only brought it up to 12ppm for night. Shock for 30 CYA is 15.

I will post full test results tomorrow.

Also your quot below:

"What I suspect is happening to a lot of people with sand filters on AG pools, is that forcing the algae through the sand filter fractures the particles, and makes them hard to filter by any method."

I wasn't really using the sand filter. Only when I opened the pool and did the first few vacuum's. Once the pool got blue/white and the green was gone I have been running on the cart 24/7 on low.

So I am not sure the sand filter breaking up the particles hold true.

I know this may seem like a long shot but I think the filters need to be back washed often, or the carts sprayed down daily.

Even though I am not getting pressure rise I have noticed when cleaning the cart the water was milky white. So I said to myself if the filter does not seem to be catching anything then what is why is the rinse water coming off the cart white?

I also found this to be true with the sand filter when I took it offline. I backwashed it before I disconnected it and the site glass was really white for some time.

So in conclusion may think its catching it but only so much. Then it must be so fine that once you get a coating it will channel around somehow. So clean the filter and let it catch another fine coating. Again and again...

I also say this because when I did get a 1/2 to one psi on low speed, as soon as I turn the pump on high the pressure goes down.

Make any sense? Hope you understand my thinking.

( I also worked in telecom R&D engineering. Have a degree in electronics from the 1980's. Been around many PH'd's most of my younger years. So I think still think like that...LOL. They used to call me the problem finder. Plumbing is what I have to fall back on every time the market tanks. 1988 was a bad one. Also 1998 and again 2009 when my last layoff happened. I have not worked since then. Stay at home dad now. )

OK I will stop babbling Ben.....

Mike NJ

[PoolDoc]

With CYA = 15, you can let FC drop to 5, if there's no sign of green and you've brushed the pool completely.

[Lawrosa]

CL 7 ( Raised to 16ppm this pm. Why? I don't know)
CC 0 ( It has been 0 for a week or more. I dont think I am fighting anything anymore)
PH 7.5 ( Its always there every year without adding anything)
Alk 80 ( was 40. Added baking soda to raise last week or so)
CYA 30 ( Ben you wrote in last post thinking it was 15. It 30. It was 0 on open but added CYA after pool went from green to cloudy. I know it was against the ammonia issue you decribe)

Conclusion:

So I have two good known filters ( Did DE test) but cannot filter whats in my pool. I will just continue to keep at shock levels and run pump on low with cartridge only 24/7 on low.

May try 2 -4 oz of clarifier I have laying around. Other then that I have added noting to my pool.

For last winter winter I could not afford the polyquat and bought leslies algea stuff in a gallon. It was blue. I added that throughout the winter. They dont have it anymore it was a discontinued item. It was 9.99. I wanted to post the ingredients but I had the same issue last year so I don't think it was that.

Thanks for all your help. I will just chug along.

Mike NJ

[PoolDoc]

At this point, trying clarifer -- but not exceeding label doses -- is probably warranted.

One of the problems we're having, is that most of us do NOT have these sorts of problem, and even if we do have algae, it cleans up quickly. So, we're not personally experienced with this situation.