Went through pool school - waste

[JamesW]

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6.1 ppm and decreases Total Alkalinity (TA) by 7.1 ppm.

50 lbs of trichlor in a 25,000 gallon pool will:
Raise fc by 219 ppm
Raise CYA by 133 ppm
Raise salt by 179 ppm
Lower TA by 154 ppm

The effect on the pH depends on the TA and the amount of time that it takes the trichlor to dissolve.

When added slowly and the TA is high, the pH will drop but it will also rise from the TA. So, the net effect will be less than expected.

 

[HermanTX]

That is, after all tablets are fully dissolved. From what I vaguely recall, 4 tablets will take about 2 weeks to dissolve fully at setting 3. So the increases/decreases are going to ramp up to that. Which is ok, since I don't mind ramping up slow. Will keep eye on pH and FC, and slowly work on getting TA lower over time.

This is great. I looked at your Pool Math Logs - it shows CYA is 15 and as you indicate it will raise slowly with the trichlor pucks. Just keep an eye on FC, with the weather in Austin (and down to Houston), although cool, the sun comes out and can burn off that chlorine since your CYA is low. Don't just assume with your pucks that you will maintain your FC above 3ppm. Recommend that you test Chlorine and pH every couple of days.
It looks like you have learned a lot in past month and have taken control of your pool. You will really enjoy it fully when spring returns.

 

[ciaka]

Thank you sir. Yes, I think I am getting the hang of it slowly. Managed to convince pool guys to stay away. Which means I will drive this bus. And with your great help, I am sure it will be fine.

Yesterday I tested pH, and was at 7.9.
Added MU to reduce to 7.3, but for some reason, when I tested pH again today, it was still at 7.9.
Could it be due to some rain that came this am?
Tested about couple hours after rain stopped.
Now, added more MU shooting for 7.3, but also am adding water to pool, maybe 1" worth.

Tomorrow we will test again.

 

[ajw22]

Yesterday I tested pH, and was at 7.9.
Added MU to reduce to 7.3, but for some reason, when I tested pH again today, it was still at 7.9.

Now, added more MU shooting for 7.3, but also am adding water to pool, maybe 1" worth.

With fill water TA of 220+ your pH will rise whenever you add fill water.

Accept that you will be lowering your pH every few days given your high TA fill water.

 

[ciaka]

Good to know. I am set to keep testing and adjusting daily if needed. It gives me practice.

How do you guys test CH. Recently during tests, it dies not turn suddenly value, but very gradually into more purple. How long do I add drops, and why purple? Been reading and it shows traces of metals? They did install the nature 2 copper several cartridge. Will last 1 month after which I will not be putting new one. Just cap once I remove that cartridge.

Any way if someone can shed light on the purple vs blue, and how far keep dropping, it will help me do this better. Thanks.

 

[ajw22]

Been reading and it shows traces of metals? They did install the nature 2 copper several cartridge. Will last 1 month after which I will not be putting new one. Just cap once I remove that cartridge.

Remove that ASAP. Do not wait and let the metals get into your water. No metals are good for pool water. They will just lead to unwanted staining.

 

[JamesW]

 

[JamesW]

Speedstir helps with getting a good calcium hardness test result.

 

[ciaka]

Roger that. Done.

 

[ciaka]

One more question. Pool is nearly month old. I'm getting thoughts to start using the robot to do some cleaning, with me touching some harder places.
Also, thinking of getting wide brush that has some steel bristles mixed with vinyl. Been reading thats what to use on pebble pool.
Thanks for advice again.

 

[Dirk]

I wouldn't use a steel brush on my pebble. Maybe if it was badly stained, but not when it was new and stain-free. I would say it's OK to use the robot. @ajw22, what do you think? @JamesW?

 

[ajw22]

There is never a reason to use a steel brush on a well maintained pool. The whole purpose of brushing the pools surface is to break up any algae biofilm that is beginning to form so chlorine can do its work. All it takes is a nylon brush.

 

[setsailsoon]

I got a set of brushes shortly after moving in. One nylon, one brass, and one steel. Even with very light use in a small area the metal ones discolored tile/plaster and removed grout aggressively. Never used them again and now I use them to clean rusty tools... banished from the pool forever.

Chris

 

[JamesW]

I would not use the stainless steel brush.

Nylon brushes should be fine.

 

[ciaka]

Great. I'll follow your advice on brushes.
How about robot, is that ok to start helping clean now? Pool nearly 1 month old since 1st fill.

 

[Dirk]

@ajw22, @JamesW, I was actually asking about the robot. OK to start using one on new-ish pebble (not quite a month old)? I know you wait at least a month for plaster, but the OP has pebble...

 

[ajw22]

Pebble and plaster the same. Eithr one can be soft enough to create tracks. Wait at least 28 days before using any wheeled cleaners, including a roebot.

 

[ciaka]

Ok. Pool pebble was put in on 5th. Acid washed on 6th, started filling 6th am, finished filling 9th night time. 2 hoses going at same time non stop.
So I assume should be ok to start using robot.
Thank you all for the help.

 

[ciaka]

Gracias seńor.

It is worth 0.2 ppm not 0.5 ppm in a 25 ml sample

 

[ciaka]

That darn pH not coming down much. Yes, my CYA is low, and TA high. But I guess it is the war that has to be won, not just one battle here.
I put in 50oz MU yesterday, and pH decreased from 7.9 to 7.7. So I cranked up the chlorinator for faster dissolving from 3 to 4 (my slow way to get rid of tabs and increase CYA), and added 64 oz MU to reduce by 0.5. I bet it will be down to 7.4 tomorrow.
Kind a enjoy this daily testing. Gives me excuse to tell wife 'gotta do something really important, that requires 100% undisturbed concentration for 1.5 hours'.