Lack of circulation issue?

[dpeat14]

Hi,

I'm having an issue with fairly constant algae growth but only on the bottom of the pool....my water is clear and balanced. I think the issue is with my pump/motor because the pool bottom area directly in front of the return jet is clean and clear. About 10-15 feet from the return there is usually a heavier build up of algae, and there is algae on the rest of the pool bottom throughout. it also stays pretty clean when it's getting used more often. I honestly think that the water is not getting circulated throughout.

I'm curious if it's possible that the pump/motor I have isn't big enough (33 ft above ground pool, 1.5 HP Hayward pump) or if there is something I need/can do to increase the pressure and the return. I can say that the return jet only shoots water out of the bottom, so I don't know if that's normal or not. I looked online and was able to find 2 HP motors, but I didn't know if that was as big as they get, or if that would even fix the problem.

thanks!

- - - Updated - - -

I also noticed I need to change my signature as I recently found out I did the math wrong and my pool is closer to 26,000 gallons.

 

[YippeeSkippy]

If you have algae, your water is NOT balanced. While circulation can be a problem in some areas your routine brushing will compensate for this and allow the FC in the water to touch everything. How are you sanitizing this pool?

Please provide us with:
FC
CC
pH
TA
CH
CYA

I think your pump is plenty big enough for the job.

 

[dpeat14]

I don't have the exact levels but last test the levels were all within normal/recommended ranges according to my test kit. To sanitize I use a chlorine tab floater and shock nightly. And this has been an ongoing issue for the few years I've owned the pool. I used to have problems keeping the water clear but that is not an issue anymore, but the bottom gets dirty. Is it possible that the pump isn't going strong enough and is there anything I can do to increase it? I clean the filter about once a week. Is there another way to sanitize that would fix it?

 

[YippeeSkippy]

Cant really say until you can get us recent test results. Can you run a set tonight? Do the CYA with your back to the sun, 'k?

We rarely suggest using pucks in a floater or "shock" products....so something is wonky to our methods here.

 

[dpeat14]

I can test again later today if that could be an issue. I only think it's the circulation because of how clean the bottom is where the pump is hitting.

- - - Updated - - -

I added CYA in June, it not shock or the floater, how would you suggest? I'm basically using what I inherited from the previous home owner, but there is a small (18-24" high maybe) canister looking device that i think may be an auto-feeder, but it wasn't hooked up when I bought the house and I don't know how to use it.

 

[YippeeSkippy]

That device sounds like an puck chlorinator...same as if you put the chlorine pucks in a floater. Is it still unconnected? What is this "shock" you say you put in nightly? Is that a liquid or granular product?

Yup, run a full set of test results please. Thankyouverymuch!

 

[dpeat14]

Yes it is still disconnected. I never knew what it was or how to use it and this homeowner left a lot of odds and ends that weren't in great or working condition, so I never messed with it. Only supply place near us is Great Escape so I use their liquid shock (12.5% strength) and their 3" power tabs in the floater. The floater also had a string on it so I tied that to the pool fence in front of the return jet...hoping it would push out more chlorine.

 

[dpeat14]

Water Test results, just recorded...
FC-1 (i typically chlorinate at night, i need to put some in soon)
CC-0
pH-7.8
Alk-300
CH-100
CYA-I ran out of the testing chemical for this test. However, I tested this at opening in the spring and it was about 15-20 and I added a couple of pounds of CYA at that time.

 

[AimeeH]

Water Test results, just recorded...
FC-1 (i typically chlorinate at night, i need to put some in soon)
CC-0
pH-7.8
Alk-300
CH-100
CYA-I ran out of the testing chemical for this test. However, I tested this at opening in the spring and it was about 15-20 and I added a couple of pounds of CYA at that time.

If you are using pucks, you are constantly adding CYA to your pool. The amount of chlorine you need is entirely dependent upon what your CYA is. "Shocking" should not be a necessity in a properly balanced pool.

Pool School - Chlorine / CYA Chart
Pool School - ABCs of Pool Water Chemistry

 

[YippeeSkippy]

Well, unless you get some more reagents ordered (TFTestkits.net) you're gonna continue having "circulation" issues that are actually lack of appropriate chlorine level issues causing that algae on the bottom of the pool issue.

Without knowing your CYA I can't advise you on how much FC you should be keeping in the water but I can say in all certainty that its more than is in there now.

 

[dpeat14]

Ok...so more chlorine is needed. I'm not supposed to use pucks or liquid shock...so what do I do to fix it??

 

[pooldv]

Liquid shock, liquid chlorine or bleach are all the same thing and all fine to use. The only difference is the percentage of sodium hypochlorite. Chlorine level is set based on the [FC/CYA][/FC/CYA].

More here, Pool School - How to Chlorinate Your Pool

 

[max2k]

Ok...so more chlorine is needed. I'm not supposed to use pucks or liquid shock...so what do I do to fix it??

If you'd like this to start making sense:

- order CYA refill from TFTestkits, the bigger the better- I have a feeling you'll need it
- remove all your floaters, etc from the pool
- bring your FC at least to 10 ppm using bleach/liquid chlorine
- brush the walls/bottom and run pump/filter 24/7 if you can
- don't add anything else to the water unless advised by the forum

when refill arrives run the full set of tests again and post results here. Currently you're way below any safe FC level.