algae and high ph

[dalejanus]

I failed to mention that we did not add any chlorine for a week because it was raining like heck every day for a week. Then we let it go for a few more days. (I know, I know) So I am pretty sure it is algae. It's green.

We went about a week and a half with out testing. I don't check calcium very often with a vinyl pool, but I'll check it tonight to be sure.

No chemicals added except bleach. Well, I think my daughter put in a floculate (stuff that clumps things together) that my wife bought at the beginning of the season, but nothing else.

I will get an overnight chlorine to see if it is holding. Once it is holding, I will lower pH. I think I still have some muratic acid with my pool stuff.

Thanks.

[aylad]

No chemicals added except bleach. Well, I think my daughter put in a floculate (stuff that clumps things together) that my wife bought at the beginning of the season, but nothing else.

Keep in mind that high chlorine levels tend to give false high pH readings. I would retest your pH when your chlorine comes back down to its normal levels before using acid to lower it.

Janet

[dalejanus]

here are my numbers from last night
fc 13.5
cc 1
ph 8.2
ta 100
cal 80
cya seems to be 0, I could always see the black dot.


We vacumed to waste last night.


This morning fc 12 and c .5


I found my muratic acid, but I can wait to put it it.

The ph was 8.2 before I started shocking.

Still green this morning, can't see the bottom.

---Dale

[dalejanus]

The pool is somewhat less green, but I'm having vacuum trouble. It doesn't always want to seal at the skimmer and since I can't see the bottom (today I can see if faintly) I was not able to tell if I was vacuuming or just brushing stuff around. Then the pin that attaches the head to the pole broke. Of course this is at 7:30pm, so I run to the pool store before they close. Pool store is closed on Wednesdays. Sigh.

So I shocked some more, now up to 25 ppm (a little more than I planned). We'll see how much it drops overnight.


When should I add Muratic acid to bring PH down? After algae is gone or do it now?

[aylad]

When should I add Muratic acid to bring PH down? After algae is gone or do it now?

Your chlorine is going to be more effective at the lower pH ranges, so bringing it down now would be fine...as long as you know your levels are accurate. High chlorine (I'd say above 10) will skew your pH test results upward, so just be careful not to drop it below 7.0. I'd shoot for 7.4 while your chlorine is high just to give you a little wiggle room.

janet

[dalejanus]

good advice, aim for the middle.

Bleach calculator says 9oz for a .2 decrease, I'll try 27 oz which should bring me from 8.2 to to 7.6 or so.

As everyone on this forum says, small steps are much better than large ones.

The pool is clearing, now its blue rather than green.

[aylad]

The pool is clearing, now its blue rather than green.

That's good news...just keep the chlorine and patience level up, and you'll be crystal clear before long!

Janet