Green pool after using Trichlor

[FJF]

My 2nd season of owning a pool and learned a lot from this sight. I have been using test strips that said my CYA was very low. Now I realize that the trichlor 3in tablets and shock add 0.6 parts for every part chlorine added. I'm sure my CYA was very high and last week I added a bunch of trichlor to shock with no effect. Time to dump my green pool. My question is, I still have some trichlor tablets and shock left, and want to use them up when I refill the pool, near as I can tell, I should use no more than 15 lbs of tablets or shock to reach 40ppm CYA? OR do I have the math wrong? How much Trichlor can I add before exceeding 40ppm for a 25kgal pool? I will switch over to either liquid bleach or the calcium based stuff in the future. I also have a leak somewhere that drops the pool 2 inches in 3 days, but have isolated it to the plumbing. That has helped delay my CYA build up problems. I live in SC with lots of sun and lots of tall trees with pollen next to the pool (crape myrtles are in full bloom).

Funny how the makers of Trichlor do not mention their product is already stabilized......

 

[linen]

Welcome to tfp, FJF

Now I realize that the trichlor 3in tablets and shock add 0.6 parts for every part chlorine added.

Yes, each 3in (assuming 8oz) tablet raises your 25000 gallon pool by 1.3 ppm cya. I used the "effects of adding chemicals" section near the bottom of the poolcalculator.com.

Before draining I would get an accurate measurement of cya so you know how much you need to drain. You never want to drain a vinyl ig pool more than 1 foot depth in the shallow end to prevent you liner from moving.

The best first step you can take is to get an appropriate test kit. See this pool school article: http://www.troublefreepool.com/pool-school/pool_test_kit_comparison Many of us have the t-100 since it is the best value.

How much Trichlor can I add before exceeding 40ppm for a 25kgal pool?

About 30 tablets, but the problem is until you get up in the 30-50 ppm cya range your chlorine will be consumed very fast by the sun and unless you can check during the middle of the day, your FC level may drop below the minimum and put you at risk for algae. My recommendation would be to save the pucks for a vacation and instead use granular stabilizer to raise your cya level and bleach/liquid chlorine to chlorinate with. See: http://www.troublefreepool.com/pool-school/types_chlorine_pool

 

[FJF]

Thanks for the quick reply! Well, I have to drain the whole pool anyway. The Algae built up so fast and so thick in just a week, it was amazing! I drained it at the end of last season and it wasn't too bad, although now I have some ideas of how to keep the liner from wrinkling. This spring we had a lot of rain and I didn't realize the well point valve was supposed to stay open? so the liner was literally floating 2-4 feet off the bottom everywhere (lots of wrinkles when it went back down). So now I keep that valve open most of the time, but I do have to close it when the ground dries out or I get too much air across the pump, so that another constant maintenance item I have to watch. Does anyone know of any tricks to keep the liner from wrinkling while re-filling their IG vinyl pool? I have also put new o-rings in my 4 Hayward valves and that has effectively stopped air bubbles across the pump strainer. But now I am wondering if that was part of my water loss problem, is it possible that the air bubbles entrap more vapor and contribute to water loss in a significant way? The valves were not leaking water, just sucking air.

Last thought on Trichlor, it seems that by the time I shock it with Trichlor a couple times a week, and use the 3" Trichlor tablets that it would only take a couple weeks to have the proper amount of CYA? Last summer I never used CYA because I didn't know any better, and got by ok...... But this summer is way different! So I want to make sure I'm doing it right. I am using the Aqua Chem 6-way strips to measure CYA which I have a lot of, but notice the T-100 kits only have enough for 8 tests or so. T-50 only has 3. With my constant change of rain water and pool leakage it can get expensive just measuring CYA, so I'd like to think I can just keep track by calculating water loss/addition by volume or keep using the cheap, roughly accurate test strips. Any thoughts?

 

[duraleigh]

TF-100 has enough for 16 tests. Way cheaper than guessing and losing all your chlorine over the season. Plus, you should only need to test CYA about 4-6 times each season.

 

[FJF]

Well, my pool is crystal clear now with good TA and FC. I am using up my 36 tablets of 3" trichlor until I reach 40 CYA (we recently had 5 inches or rain, so I can use some up my trichlor shock too).

I am now on to fixing my leak which is about 1inch per day. I have isolated it to a return pool line using the dye test. I have 4 returns, two by the steps that joint to one valve at the pump and two that are opposite sides of the pool, also joined to a 2nd valve. The 2 valves are manifolded after the pump. Of the two returns that are joined somewhere under ground, only one sucks in dye which tells me the leak should be closer to the one return than the other, being a longer distance. So I'm ready to get my shovel out but 1st stick a plastic fish tape down the pipe hole to find that it takes a a turn down for a number of feet before going to the house. I really wasn't counting on digging down 6 feet or more to find this leak. Probably 100ft from the pump valves to the pool return. Does anyone know of any tricks to isolate the leak as a function of how far down the pipe it is? The pump runs at 12psi anyway and I can't find any greener grass or other visual indications.... Is there any product like "Stop Leak" that could be used? The only other piece of data is the the pool level stops leaking right at the bottom of the strainers, which fooled me for a long time (thinking is was the strainers or piping that leaked). So the leak in the return pipe should be relatively shallow in the ground?

This reminds me of an old Three Stooges episode in the making.......

Appreciate all the help, I have learned so much here and become a lot less frustrated maintaining my pool.