Indoor pool chemical troubles

[rgs36]

Hello

I have an indoor pool of about 54,000 litres. Since we had it setup about a year ago by a company, I've kept it topped up with chlorine via and feeder and the levels have all stayed stable. CYA is very low.

However I recently decided to shock it as I thought it was a good idea. I probably put in a little too many granules as initially a strip test didn't show the FC levels going up. I probably put enough in to raise it to around 14ppm.

However, 5 days later, the chlorine level is still very high. Further, when I test the water with a strip it is telling me that the pH is too low, yet when I test it with a liquid test (Phenol Red) it is telling me the pH in the right range. I'm now not sure which to believe or what to do next.

Many thanks

 

[mknauss]

Welcome to the forum!
Sadly, you have limited resources for proper pool water chemistry testing kits. Strips are garbage, throw them away.
The drop test for pH is accurate as long as your FC is under 5 ppm.
Read Pool Test Kits - Further Reading
I suggest you read through Pool Care Basics - Trouble Free Pool and even look at a few of our videos TFP-TV - Trouble Free Pool

 

[PoolStored]

This is currently your best bet for a test kit in the UK. - Amazon.co.uk - it's the "smaller" Taylor kit that's normally recommended around here. You can buy refills for the main tests you'll use up from Amazon.com. It's a slight gamble on what the expiry date is going to be buying these from Amazon but there aren't any other good options.

If you store them in a cool, dark location they can last a couple years. Also depends how long they have been sitting in the Amazon Warehouse.

 

[rgs36]

Thank you

What would you recommend that I do to the chemical levels so I can get swimming again ?

Use a chlorine reducer to get it back down, then check the pH level again once it's down and adjust as necessary?

Many thanks

 

[Bperry]

Thank you

What would you recommend that I do to the chemical levels so I can get swimming again ?

Use a chlorine reducer to get it back down, then check the pH level again once it's down and adjust as necessary?

Many thanks
Richard

Get the kit on order and test the chlorine level. The strips provide no accurate data.

 

[rgs36]

Get the kit on order and test the chlorine level. The strips provide no accurate data.

I've tested with a DPD tablet and that says that my chlorine is very high. Is that an accurate measure ?

 

[Bperry]

I've tested with a DPD tablet and that says that my chlorine is very high. Is that an accurate measure ?

Very high is not very precise. And if your stabilizer level is also very high then your chlorine may actually be too low. Those two measurements are intertwined and you can’t judge one too high or low without knowing the other.

 

[rgs36]

Thank you

At the moment (until I buy a better kit) the only measurement for CYA I have is from the strip, which shows close to zero and has always shown close to zero since I have had the pool. Can I trust this?

The tablets I have used in the doser are stabilised but I have used unstabilised chlorine shock

 

[mknauss]

If you have added stabilizer (even by using trichlor), then your water has CYA in it.

 

[rgs36]

Ok thank you

The warranty for my heat pump says that I must keep the free chlorine between 0.5 and 1.2ppm. This seems potentially very low, depending on cya levels. How do people deal with this ?

 

[mknauss]

Ignore it. You will not have a pleasant experience trying to keep FC levels so low.

 

[jakeblat]

Hi @rgs36 I'm in the UK with an indoor pool and can recommend getting hold of the Taylor K2006 kit from Amazon linked above. The availability of test kits here is very limited and I've tried almost all of them (here's an older thread where I detailed what I tried UK Pool Test Kits)

The Taylor kit isn't cheap here and can be hard to get refills for, however it does provide the most accurate testing that will let you make informed decisions about looking after your pool. I spend about £40 a year on chemicals (mainly liquid chlorine) to manage my pool.

I've had my indoor pool just over 2 years now and manage the chemicals/water and winterisation (as some of my equipment is outdoors) myself with the help and guidance from this forum. The first step is to get accurate test results and only the Taylor kit can really do that.

 

[rgs36]

Thank you

How often should I be shocking my pool?

I hadn't shocked it for a year and had no problems with it, but after some heavy use I decided to do it and that's where I've got myself into a muddle

 

[jakeblat]

If you follow the Trouble Free Pool philosophy that was linked above (Pool Care Basics Archives) you won't ever shock your pool. I add liquid chlorine once a week, or every other weeks when the pool isn't used much and nothing else (other than when I refill the pool with a lot of hard water).

You can see everything I've added in my Pool Math app logs to give an idea of how my indoor pool behaves - PoolMath Logs

 

[jakeblat]

I normally buy a 4 pack (20 litres) of liquid chlorine at the start of the year and that's enough for my 26,000 litre pool - Amazon.co.uk

 

[rgs36]

Thanks for the info

I have a tablet feeder plumbed in, so I'm keen to keep using that, but I'm assuming the same principles apply.

I'd read that it is advisable to shock a pool every so often even if there are no signs of algae. Is this not correct ?

 

[mknauss]

 

[rgs36]

Also, what is general opinion on palintest test tablets ?

 

[rgs36]

Thanks!

 

[Bperry]

I'd read that it is advisable to shock a pool every so often even if there are no signs of algae. Is this not correct ?

Not correct. There’s no need to shock it ever if the right amount of chlorine is in the water.