new user, old pool, trouble with algae

[PoolDoc]

I'm getting a test kit for high chlorine levels and some bleach today, I'll report back as soon as I can retest.

The locally available "high chlorine" tests are not what you need, 98+% of the time. Get a K2006 or K1515 (test kit page linked in my sig) online. Meanwhile, get a local OTO (see kit page) kit for now. If the Walmart's in your area have the HTH 6-way, those are an excellent value (they are a private label Taylor kit!).

[ksukris]

I ordered a FAS-DPD kit from Amazon, found out the hard way they aren't sold at the pool stores! I did get an OTO kit, but had to dilute the water substantially to get a reading. Assuming my dilutions were accurate, I'm somewhere around 35 ppm on chlorine. Running filter and keeping an eye on pressure to backwash, and brushing daily. Would it hurt to dump in a couple bottles of bleach or should I save it for when my chlorine drops? I'll test again in the morning and see if it's still around 35 ppm.

[PoolDoc]

Unless you have EXTREMELY high stabilizer, 35 ppm is more than enough. If your chlorine level gets too far ahead of your stabilizer level, you can begin bleaching your liner. That may happen anyhow -- liners vary widely and unpredictably in their color-fastness -- but unnecessarily high chlorine can certain accelerate it.

[ksukris]

An update: Wednesday night and Thursday morning chlorine level was holding at 35 ppm. By Thursday night, it had dropped to about 24 ppm, so I added my first dose of liquid bleach and raised it up to 32 ppm. This morning, I was reading back around the 24 ppm range, so more bleach went in. I maybe detect a small change in the water color (still cloudy light green), but can't be certain. Equipment is running fine, I've backwashed a couple times and continue to sweep. The water seems to be using the bleach faster than it was using the powder shock, does this indicate anything? Shouldn't I be seeing some results with these high chlorine levels?

[PoolDoc]

Without knowing what your stabilizer level is, it's hard to say what should be happening. If your CYA=400 . . . then, no, 35 ppm won't be enough. That's why we want a CYA test. Did you check to see if a HTH 6-way was available in your area?

I'm reluctant to tell you to go higher, lest your have LOW CYA, and bleach your liner. By the way, with OTO, 35 ppm is dark orange, without any dilution.

One quick check: are you using DISTILLED water to dilute? Most tap water has chlorine, more than enough to cause testing error, if you are diluting.

[ksukris]

CYA tested to 200 ppm. Yikes! I've been keeping shock level around 35 ppm of chlorine. Yes, I'm using distilled water to dilute, I did a quick check with full-strength pool water and got a deep orange color. As for my liner, it only has a couple years left anyway, is there any other danger to overshocking? I don't plan on jumping in anytime soon Just stocked up on more bleach, in the past 6 days I've added 16 gallons.

[PoolDoc]

With 200 ppm CYA, 35 ppm is NOT over-shocking . . . if the water is clear, feel free to swim.

(Don't tell the local health inspector -- he hasn't read the Best Guess page -- but the local country club pool I service was at CYA=100 and FC=28 most of this past weekend. Over 400 people swam, with no complaints!)