SWG Startup with Algae?

Archos

0
Jul 9, 2008
27
Evansville, Indiana
I've been lurking these forums for quite awhile now. My wife and I decided to go with a SWG after having our first child. This will be my seventh year as a pool owner. I opened the pool up this year to the normal load of crud accidentally getting dropped off the cover into the pool water. After fighting with the ensuing pool chemistry nightmare this usually causes me, all I needed to do was drop the TA to 120 and vacuum before adding the salt and starting the generator. Everything was going along fine until we left for a three day weekend and left our house sitter in charge of adding a gallon of bleach to maintain the chlorine level. Instead, she took our dogs for a swim in it and then forgot to add the bleach. I came back to the greenest pool I've ever witnessed. 0 FC, TA at 240, and a Ph that was so reddish purple I could only assume it was over the 8.3 mark.

I first raised the FC level to 15 by adding 3 gallons of 6% bleach. (I now read that I should of raised that to 30 with the 80 CYA I have) After that had zero effect on the algae, I then went out and bought Algaecide and poured that in an hour ago.

My question is this: even though I have a green sewer, can I still add the salt and start the SWG or should I wait until the algae is hopefully dead?
 
Welcome to TFP!

You can go ahead and add salt, but you shouldn't turn on the SWG until the chemistry is in better balance. It isn't the algae alone that is a problem, but importantly the high PH and TA.

Did you bring down the PH? You don't want to leave the PH way high.

We can give you more specific advice if you post a full set of test numbers.
 
Oops. Forgot to mention I dropped my PH. I have the color is somewhere in between the 7.6 and 7.8 rand... so I'm guessing that's 7.7. My FC test only measures to 5, however I have maintained a supper bright yellow reading every day for the last 4 days. I can't seem to find any other OTO tests that measure beyond 5.

FC: 5+
PH: 7.7
TA: 180
CYA: 80
 
It would be really helpful to have a FAS-DPD chlorine test. It will reliably measure FC levels up to 50. The TF Test Kits TF100 and Taylor K-2006 contain a FAS-DPD chlorine test, and they are also available separately.

As a stop gap you can use dilution with the OTO test to measure higher levels. The precision is pretty bad, but better than pure guessing. You need some water that doesn't contain any chlorine. Distilled water is a good choice, though most well water is chlorine free. Mix one part of pool water with three parts of distilled water. Test the mixture and multiply the result by four.
 
So, you're telling me that even though it says:

DuPontâ„¢ Pool Care Algaecide
Available in 1 qt bottles.
The weekly addition of 4 oz per 10,000 gallons of DuPontâ„¢ Pool Care Algaecide prevents the formation of algae in your pool water. Algaecide prevents algae growth and contains a clarifier to eliminate algae and algal debris from water. Add 8 oz per 10,000 gallons at start-up, and 24 oz per 10,000 gallons to treat visible algae.

That it doesn't eliminate algae?

Or is it just stopping it from growing while the chlorine kills it?
 
Algaecide does kill algae, but it is rarely effective when you have a significant algae bloom. There is simply too much algae for the algaecide to kill all of it. And if you don't kill all of the algae, it just grows back. Because of that, the price, and the frequent side effects, chlorine alone is normally a better choice.
 

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JasonLion said:
Algaecide does kill algae, but it is rarely effective when you have a significant algae bloom. There is simply too much algae for the algaecide to kill all of it. And if you don't kill all of the algae, it just grows back. Because of that, the price, and the frequent side effects, chlorine alone is normally a better choice.

Good to know, thanks Jason!
 
Well, the pool was still green in the morning. Not quite AS green as it was, but still to the point where visibility is only about 2 feet down from the surface. I had to buy more of the PH Down Crud from the pool store. I went to both our Lowes and the Home Depot and could not find muriatic acid at any of them. I tried the pool, cleaning, and concrete sections in them. Our pool stores only sell the PH down dry stuff. I bought it and dropped the PH down to 7.2. Oddly enough my chlorine level went to .5ppm. Can you order muriatic acid off the web from somewhere? I'm at a loss where else to check for it in the Evansville, Indiana area.

FC: .5
PH: 7.2
TA: 150
CYA: 80

To raise my FC level to the recommended shock level of 30. It said to add 11.9 96oz. bottles of 6% bleach. Instead I read that as 11.9 174oz bottles... so... I think that will raise the FC level to 55 according to the Pool Calculator. Will that hurt anything? I sure as heck ain't swimming in it.

After six good seasons with a pool, I can't seem to do anything right this year.
 
With a vinyl liner and a CYA level of 80, I don't recommend raising FC above about 45. Higher FC levels are going to start fading the liner. The effect won't be dramatic from only a short period at high levels, you might not even notice it, but going outside the bounds isn't a good habit to develop.
 
Archos said:
I had to buy more of the PH Down Crud from the pool store. I went to both our Lowes and the Home Depot and could not find muriatic acid at any of them. I tried the pool, cleaning, and concrete sections in them.

Try the paint section. Up here every hardware store carries it. If all else fails, ask someone in the store!
 
Archos said:
Now if I could only find muriatic acid. I feel like I'm on the Quest for Fire.
Allow me to pass the torch...

Go to Rural King.
:wink:

There are 2 in Evansville:
2800 N Saint Joseph Avenue 812.422.0445
&
2300 E. Morgan 812.473.5750

The Rural King here has gallon jugs for about $5.
 
Awesome. I found it at the Ace Hardware in Newburgh. I'm not sure why, but people give you the strangest looks when you tell them it is for a swimming pool. The girl working the register asked me what I needed it for. When I told her it was for a swimming pool to adjust the PH level, she acted like she couldn't believe anyone would swim in a pool that had acid poured into it.

Eh... thanks for the Rural King idea. I should of known any place that would carry horse semen injectors would carry muriatic acid.
 
'ya gotta' love Rural King! :lol:
FWIW, Rural King carries TRANSCHEM which has swimming pool directions on the label. ( :roll: No, I'm not crazy--thank you very much.)
Of course the looks I got from strangers didn't hold a candle to the look my husband gave me when I said we needed to put muriatic acid in his brand new pool! ( :shock: That's what you use to etch concrete!!!!!)
He felt better when I was able to get muriatic acid from the pool store--Town & Country Pools in Newburgh. They carry... (drumroll please) TRANSCHEM!
It's even in the exact same jug as Rural King's, but it's closer to $10/gallon if you buy it a T&C. Hmmmm... it might be worth the extra money to know no will look at you like you're the Unibomber. :lol:

Good luck with the algae!
 
LOL!

Well the pool is turning a bluish color now. I went to Leslie's to try to get a FAS-DPD kit. All of their kits including the $90 kit only read chlorine to 5ppm. In order to read higher it instructed you to dilute the pool water with distilled water. I found one FAS-DPD kit that said it read up to 20ppm. The Leslie's employee said they were discontinuing it and would not be able to buy refills from their store. She couldn't even guarantee that the company who made it would still sell refills. I then asked her if they sold Saltwater Chlorine Generators. She said they did. I then asked her if she knew what they recommended the FC level was. She told me 5-6ppm (like mine). I then asked her what they sold those people to test their Chlorine with. She said that she recommended they bring their water in to be tested by them. I'm not sure who in their right mind would drive to the pool store every day to test FC, but it's not me.

I'm ordering the TFP Kit from this site. I'm also adding the salt now that I can see past the second step.
 

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