How many TriChlor tabs to last for 5 day vacation?

[sws1]

I have been using liquid chlorine to maintain my pool. I'm going away this Wednesday morning, and will be returning Sunday evening. 5 full days. I'd like to use some leftover TriChlor 3" tabs in the auto-dispenser attached near the pump to get me through those 5 days.

Question: Assuming I turn the knob on the dispenser all the way up...how many tabs should I put in?

Details:
25,000 Gal pool - Vinyly
CYA 40-50
pH 7.7
TA 100-110
Direct sun from 9am to 4pm


I usually pump FC up to 7 once a day, and it drops down to somewhere between 2 and 4 depending on weather and num of bathers. On average, I put about 80oz of 12% Bleach in the pool daily.

Thanks

 

[anonapersona]

Re: How many DiChlor tabs to last for 5 day vacation?

You can do the math using the Pool Calculator. At the bottom, Effects of Adding Chemicals, weigh age tablets, then enter that weight. I assume you know how much chlorine you typically use daily. Add some for safety, leaves or rain, and see how many that would be. Wouldn't hurt to go to higher FC with bleach before you go.

 

[sws1]

Corrected my post. I meant TriChlor.

 

[sws1]

Re: How many DiChlor tabs to last for 5 day vacation?

You can do the math using the Pool Calculator. At the bottom, Effects of Adding Chemicals, weigh age tablets, then enter that weight. I assume you know how much chlorine you typically use daily. Add some for safety, leaves or rain, and see how many that would be. Wouldn't hurt to go to higher FC with bleach before you go.

What the calculator doesn't help with is the affect of using a Tab which releases its chlorine over time. I can read the container to see how much chlorine each tab contains, but i don't know how long it takes a tab to dissolve. If it dissolves in 1 day, my FC will spike, then drop below target the other 4 days that I'm away. Won't it?

 

[Diver]

sw1, you have to experiment to see how much FC output you'll get from your chlorinator. it depends on your chlorinator and the water flow rate.

i might be in similar situation in a month, so i plan on trying it out up front and "calibrating" my chlorinator dial. once i know how much each unit on the dial means in FC output terms, i could set it accordingly

 

[sws1]

sw1, you have to experiment to see how much FC output you'll get from your chlorinator. it depends on your chlorinator and the water flow rate.

i might be in similar situation in a month, so i plan on trying it out up front and "calibrating" my chlorinator dial. once i know how much each unit on the dial means in FC output terms, i could set it accordingly

Hmmm - Not alot of time for that. I get 1 24hr period to try something out, and then I'll guess when I leave on Wednesday.

 

[Diver]

sw1, you have to experiment to see how much FC output you'll get from your chlorinator. it depends on your chlorinator and the water flow rate.

i might be in similar situation in a month, so i plan on trying it out up front and "calibrating" my chlorinator dial. once i know how much each unit on the dial means in FC output terms, i could set it accordingly

Hmmm - Not alot of time for that. I get 1 24hr period to try something out, and then I'll guess when I leave on Wednesday.

i would go higher then i think needed and then would interpolate.

 

[Durk]

If it hasn't been used for a while I would start it operating full blast right away--valve all the way open and a full load of tabs. Check FC and wait 24 hrs. If it is stable or slightly lower, you'll be fine for 5 days. If it jumps, then back off your valve by a third. If it drops as if no FC was added, it's not working so go buy a floater.

Or just buy a floater and load it up with the vents wide open--works in my 28K for a week, yours should be fine, too. Five days is not that big a deal as long as SOME chlorine is getting into the pool. Floaters are much more reliable than auto-chlorinators.

 

[anonapersona]

If you shock for a day or two before you go you may be able to reduce that daily consumption a bit. 4 ppm a day seems a bit rich.

If you were able to lower that by some, you'd be in better shape and not so much at risk if FC fell due to a storm or whatever.

How much time is left? Can you do a proper shock in the days remaining? Get to shock and hold it there??

 

[sws1]

I just did my daily bleaching. The chlorine dropped roughly 3 ppm in 24 hours (dropping from 6.5 to 3.5). But some of that was used to clean up from the 8 people that were in the pool just prior to yesterday's bleaching.

SO - I raised it back up to 7 today. And I also put 5 tabs in the auto-chlorinator with the dial set to wide open. I'll check it later, tomorrow morning, and tomorrow night to see if I'm going up or down. I probably can't add anymore than that. So I suspect I'll end up lowering the dial a bit.

Last year, when the "pool people" were maintaining the pool (cya of 200), they'd put in 4 or 5 tabs a week in the chlorinator (wide open dial), plus a weekly shocking. I'm hoping the chlorine usage is about the same.