algae

I opened up my pool memorial day weekend and finally got a clear pool a week later, BUT yesterday I noticed some algae starting to form on the wall. I brushed and vaccum on waste. It has been in the 90's here for a week and a half. My numbers are within spec based on this website recommendations.

How long should I run my pump?
How often vaccum the pool?
How long should I run my kreepy krawly?, I don't use it much at all.
Do you chlorine tablets hurt? I bought some on sale last year at a good price at Lowes.
I have a inground vinyl pool 20 X 40 around 36000 gal.
I had the same problem last year with the algae and my numbers were always in range.
Sorry for all the questions

I run my pump 12 hours per day, when I'm not fighting algae. Since you have algae, leave the pump on all the time. And get the FC level up to shock level.

I vacuum my pool when I see something that needs picked up. Which usually works out to once per week. I brush more often than that.

Since I don't have a kreepy krawly, I'll pass on this question.

Chlorine tablets come in different kinds. The tri-chlor ones with stabilizer will increase your CYA and decrease your pH. Once your CYA gets to 50, I think you should stop using the ones that contain stabilizer. I have seen other tables that contain cal-hypo, and do not contain stabilizer. Those will increase your CH (calicium hardness). I forget what the upper limit is for CH is a vinyl pool, I think it can lead to cloudy water if you go past the upper limit.

You should post your numbers so that the pool experts here can give you better advice.

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Originally Posted by jimk0512

You should post your numbers so that the pool experts here can give you better advice.

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Yep. We need to look at numbers to be able to offer advice. Repost with current water testing results from a drops-based kit (not teststrips) and somebody here can help you get your pool cleared.

ph 7.3
alk 170
cya 45
tc 4.0

the tablet I bought are by Dupont sanitizer 3" chlorinating tablets
99% trichloro-s-trizainetrione with available chlorine 90% and 1% other which it doesn't say what it is

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Originally Posted by hannadock

ph 7.3
alk 170
cya 45
tc 4.0

the tablet I bought are by Dupont sanitizer 3" chlorinating tablets
99% trichloro-s-trizainetrione with available chlorine 90% and 1% other which it doesn't say what it is

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The tabs you have are trichlor, which are raising your CYA as we speak. Your CYA is at a point where you already need to keep a minimum of 3 ppm chlorine, and preferably closer to 6. I would definitely stop using them now and switch to bleach as your chlorine source. To clear up your algae, you need to add chlorine to the pool til you get to 15 ppm and keep it there, with your pump running 24/7, until the pool goes to cloudy blue. You'll need to test and add more bleach 2-3 times daily until this happens. When the algae is gone and the water is cloudy blue, then keep your filter running but you can let your chlorine drop back down to the 3-6 ppm range, but NO LOWER than 3.

Brushing your pool daily during this process will speed it up, and running the vacuum certainly won't hurt.

Janet

thanks I will let you know what happens

alright. I put more than 10 gallons of bleach in Saturday evening now my level are terrible. Everything look good yesterday.

chlorine less than 1.3
ph around 7.7
alka 200
cya 35.

my slide has started to turn yellow from the bleach which it hasn't before. My alka has always been within range but after the rain came up. My ph has risen and looks like my cya has gone down. I have scrubed my walls vacumned on waste. Let my pump run non stop. At present my pool cleaner is running, just turned it on. HELPPPPPPP. I am wasting money

Is there a difference between the Walmart brand of bleach and Chlorax.

What are you using to test? Are you using strips or a drop-based test? Keep in mind that test strips are not accurate enough to help correct a problem--they give you a ballpark, but you really need accurate numbers to fix problems. If you don't have a drop-based test, you need to get one.

Once you have algae growing, you have to maintain a shock level--key word MAINTAIN--until you have killed the algae. With your CYA level, you need to get your chlorine up to 15 ppm and keep it there by testing and adding more chlorine 2-3 times daily until the algae dies. It won't help to shock it once, then let your chlorine come down. 10 gallons of 6% bleach will raise the chlorine in your pool to approximately 16 ppm--but if you haven't add any since then, you're not going to make any progress against the algae, since the chlorine is being used up in the battle against the green stuff.

Bleach will sometimes cause a temporary rise in pH, and high chlorine levels will often cause the pH test to give falsely high results. If your slide is turning yellow, and you are using test strips to test your water, I strongly recommend that you have the water tested using drop-based testing to make sure you really know what your chlorine level is. If it's not at 15, then you need to get it there and hold it there to kill off the algae.


WalMart bleach (generic) is 6% sodium hypochlorite (chlorine). Clorox is also 6%, I believe ( you can look at the label to confirm). However, clorox has started adding another ingredient to the bleach that is designed to help lift stains, but can appear in pool water as a white sediment on the bottom. WalMart bleach is cheaper and has no added ingredients (as long as you stay with the plain ultra bleach and make sure you're not buying the stuff with the scents added--you don't want that).

Janet

I am using the drop based testing kit. I have 3 different ones and use all 3 when my results are bad just to see. All 3 gave the same results. Should I be concerned about my CYA. thanks

Cya of 35 is fine. Jan is giving you good advice. You'll soon get that pool clear!

ok for the last 6 days I have been dumping the bleach in. No algae but my water is cloudy. I can see the deep in but very little. I have been cleaning, vacumning on waste. what next? thanks for the help

Post current numbers.

ph 7.6
alk 180
cya 35
tc 11.0

A couple of questions. How many times a day are you testing and dosing with bleach? Is your chlorine level dropping off low before you shock it back up again? When you dose with bleach in the evening, are you still losing a lot of the chlorine overnight? Do you know your calcium hardness reading? Also, how much run time is your pump getting? You should be running it 24/7 while trying to clear your water. If your algae bloom really is dead, it may take a few days to let your filter clear the dead algae.

I test in the evening and shock in the evening 4.5 gallons. I run 24/7. I don't know my calcium hardness off hand. I didn't think that applied to vinyl liners.
I running my cleaner 2 to 3 hours in the evening. I noticed the chlorine dropped off after missing a day. thanks for you help

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Originally Posted by hannadock

I don't know my calcium hardness off hand. I didn't think that applied to vinyl liners.

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It only matters if Calcium levels are too high. If your Ca reading is something like 500 or 600, and your T/A is 150-200, you are going to get cloudy water. Even with more appropriate T/A levels you may get cloudiness.

Calcium is totally unnecessary for maintaining the water in vinyl pools. What that means is when the Pool Store Guy tries to sell you calcium additives "because your calcium is low", you shouldn't waste your money.

But that doesn't mean if it gets too high you cannot have problems.

I will check and repost. thanks everyone for the help

ph 7.7
alk 210
cya 35
tc 11.0
hardness shows very little.