Pool Chlorine/unstabilized

First of all, thank you for BBB method. It works great and my wallet thanks you.

My pool guy tested the pool and recommended we start using un-stabilized chlorine as CYA is at 100 now. Pool is in-ground around 26K gallons and had no real issues with it so far (only my second year since we bought the house).

I did have an incident where I learned not to combine stable and un-stable chlorine in same chlorinator. Luckily nobody was hurt besides my ego and neighbours enjoyed the firetrucks...

I have bought 50 lbs of chlor-hypo 3" tablets and it seems that I perhaps should not use them as it makes my pool water foam and milky. Is that normal? What should I use to chlorinate my pool with if not using those tablets? I have not added anymore chlorine/bleach as levels look stable around 5.

My last readings were:
Both chlorine levels at 2 (Leslie's) - my home kit shows 5-10
PH - 7 - 7.2
Alk - 100
CYA - 100

I don't have my complete sheet with me but will update later.

Thanks in advance.

Hi, and welcome to the forum!!

First off, I'm glad nobody got hurt in the chlorinator incident--I'm assuming you're talking about an inline chlorinator, as opposed to a floater? You are right in not using anymore trichlor tabs due to your stabilizer being so high--but keep in mind that the cal-hypo tabs are not to be used in an inline feeder. There's something about the amount of heat and the speed at which they dissipate that makes that a dangerous proposition, so if you're going to use the cal hypo tabs, use a floater. One of the chem levels that you didn't post was your calcium hardness level--when you calcium levels get too high, then using the cal hypo will cause milky water. So....your best bet is to switch to plain, unscented bleach, or liquid chlorine if it's available in your area. Liquid chlorine is the same as bleach, but at a 12% concentration, where ultra bleach is a 6% concentration. In a pool your size, each gallon of 6% bleach that you add will increase your chlorine by just over 2 ppm, so you can use that as a guide. I want to caution you, though, that with a CYA of 100, you need to be keeping your chlorine levels absolutely no lower than 8 ppm, or you're inviting an algae bloom. It would be better to try to keep it closer to 10, so that you have a little wiggle room and don't ever go below the 8 ppm. You can use the link to the "best guess" table to see what levels of chlorine are adequate for what levels of CYA.

Janet

What kind of filter do you have? Do you have a heater?

There may be a way to use the tabs successfully.

I do have DE Hayward filter and natural gas heater.

Incident was in the in-line chlorinator and it was pretty violent (inside of it). Nobody got hurt and I learned a lesson. You are correct of being very quick to disolve and produce heat.

My today readings are:
FC - 3-5
TA - 80
PH - 7.2
Calcium Hardness 120
TDS 600
Phosphates 500

Thanks for all your help.

You need to get some chlorine in the pool, or you're going to have an algae problem. See post #2 above...

Janet

Thanks Janet. Any way I can still use my cal-hypo tablets?

Sergej

There's no 'standard' way to use your cal-hypo tablets, given your other conditions (heater! and feeder!).

There is a NON-standard way, but I'm not going to tell you how until you have
#1 - A Taylor K2006 or 2006C or equiv (Amazon links below); &
#2 - You've gotten your pool chemistry under control and running smoothly.

This method will actually produce improved water quality, BUT is dangerous if you don't understand and follow my instructions.

Ben