problem with chem with a indoor pool

[jasongsd]

I have a 15000 indoor pool that were always having trouble with. Here is whats been going on. Pool inspector came in a few weeks ago and the cc was at 1.0 should be lower then .05 so he closed us. were have been trying a few things to figure out how to do this. We have windows on the north side but never gets any sun. We closed the doors leading out side and the cc goes up. We open the doors going outside and everything is perfect.

well we cant leave the doors open because of a safety concern. The ventalation in the pool sucks. no pun intended. I have a exhaust fan pulling out moist air but theres nothing to bring in freash air. Any ideas in how to bring in fresh air?

Also we have a spa in there also. So it seems like there always fighting each other with the chem's.

 

[whoozer]

If you have a cc of 1 that means you need to shock your pool. cc's are the presence of algae (organics) growing in your pool. Whether you have windows open or whatever shouldn't be affecting your pool chemistry. Shock your pool, ventilate if you have too, it still shouldn't change your chems. Get that cc to 0. Keep shocking until your cc-0 and you have less than 1ppm FC loss overnight.

 

[JasonLion]

Welcome to TFP!

Ventilation is extremely important. Anything you can do to increase the ventilation is good. Can you open up the North side windows?

Have you tried using MPS (Potassium Monopersulfate)? It can often help keep CC down in and indoor pool.

 

[whoozer]

I would def listen to JasonLions advice over mine....much more knowledgable about pool issues than me

 

[jasongsd]

I shock the pool everytime the CC is high. And the windows are not able to open.

 

[257WbyMag]

MPS would be the next most logical step to take care of those CCs. Because indoor pools can't take advantage of UV rays from the sun to break down the CC, you have to handle it chemically.

 

[jasongsd]

I will pick some up tomorrow and give that a try.

 

[PaulR]

Be aware that MPS can show up as CC so either get a test kit specifically designed to handle that, or wait maybe a day after adding MPS to test for CC again. Somebody with a better handle on how the MPS/CC relationship works may have improvements on my suggestions.
--paulr

 

[Richard320]

How about some more info, or some pictures? That might help us brainstorm ventilation ideas.

I'm guessing this is a gym or a hotel. If it's a hotel, what about opening those doors when the pool is closed and people are asleep? Or put a screen door up. If it's a security door, there are plenty of wrought-iron security doors available. Very common in the rougher areas of LA. They allow full ventilation yet can be deadbolted. Many have a screen in them, so they just look like an ornate screen door.

 

[frustratedpoolmom]

You should read Pool School - start here:
Shocking Your Pool

You'll need one of the recommended test kits:
Test Kit Comparison

While the shock process is going on read these two:
How to Chlorinate Your Pool
How to Use Chlorine in your Spa
And then move on to the remainder of the Pool School articles. What do you use to chlorinate the pool and spa on a daily basis? What are you testing with?

 

[chem geek]

Pool inspector came in a few weeks ago and the cc was at 1.0 should be lower then .05 so he closed us.

Are you sure he said the CC had to be lower than 0.05 ppm? Are you sure that isn't 0.5 ppm or perhaps 0.2 ppm? I've never heard of a requirement to be below 0.05 ppm and the lowest resolution for CC in the FAS-DPD test using a 25 ml sample is 0.2 ppm. The ANSI/APSP-11 standard states that "The concentration of combined chlorine in pools shall not exceed 0.2 ppm."

If this is a commercial/public pool, then with high bather load it is going to be extraordinarily difficult to keep CC low without the use of some form of supplemental oxidation. Usually, this entails use of either UV or ozone though as Jason mentioned sometimes non-chlorine shock (MPS) is used in which case the Taylor K-2042 MPS interference remover is needed for an accurate reading. Also, as you've discovered, proper ventilation can remove volatile disinfection by-products so that they do not build up as quickly in the pool. Perhaps you can vent during a part of the day/night when someone is present to handle the safety concerns.

What is your source of chlorine for this pool? By any chance are you using Trichlor pucks (perhaps in an inline chlorinator)? If so and if the CYA is higher than 20 ppm, then this can lead to excessive monochloramine buildup as well as chlorourea since the effective chlorine level is reduced significantly leading to much slower oxidation of chloramines.

Richard