Drain and refill, can't recall chemical order/procedure

[mprzybylski]

I am having to drain my pool (finishing today) due to high CH/salt and will start refilling immediately when complete. I remember when I initially started up my pool, there were certain aspects and order that the chemicals were added to ensure proper balancing, and there was one in particular that you had to keep the SWG off while adding (I think it was CYA, but it wasn't a problem before because I didn't start my SWG until 30 days after anyway, though I do recall reading that it should be off if adding whatever it was). I tried to re-read the ABCs but it does not give this info and I can't remember where I found the proper order/procedure and what should remain off when balancing your water initially. Is there a link to this guide that I can't find?

And if not, what should be the order of adding chemicals to get my water back in balance properly?

 

[mknauss]

Once well mixed, run a full test (exc CYA). Add 3 ppm FC worth of liquid chlorine. Get 30 ppm CYA worth of stabilizer dissolving. Adjust pH to the 7's. Add salt as necessary. Do not have the SWCG on when adding salt and until the salinity is well mixed.

 

[mprzybylski]

Once well mixed, run a full test (exc CYA). Add 3 ppm FC worth of liquid chlorine. Get 30 ppm CYA worth of stabilizer dissolving. Adjust pH to the 7's. Add salt as necessary. Do not have the SWCG on when adding salt and until the salinity is well mixed.

ah, it was the salt addition to keep the SWG off, thats right.

A few questions:
1. How about TA? When do I add baking soda into the mix?
2. What is the reasoning for using liquid chlorine versus using the SWG? I'm assuming because there is no salt in the water until I add it, which comes at a later step, so the initial push has to be with liquid chlorine until I can get the salt well mixed at which point I can use the SWG to produce chlorine?
3. What should I do about my CH? This is the main reason I'm draining in the first place, so I want to make sure I get this right. I presume I'll be on the low end after the fill but am hesitant to add anything to make it rise.

 

[mknauss]

With your fill water, you should never need baking soda. Measure TA to be used in Poolmath, but just manage pH in the 7's.
You need chlorine with a fresh fill. Use liquid chlorine. Your SWCG will stop generating here in a few weeks (water temperature of 52F) so you will need to use liquid chlorine until the water temperature rises above 52F
Your fill water CH should be about 250 ppm. No need to add calcium. Using softened water after the initial fill will greatly reduce your CH rise over time.

 

[mprzybylski]

@mknauss great, thank you. I did recently have a soft water bib installed by my pool equipment and added a line to the autofill to switch between hard and soft water so I'll set it to soft after fill and hopefully that keeps my CH problems at bay.