So I've owned a pool for about 4 months now. When I bought the house the first thing I did was get on this site and start learning...it led me to drain the pool that has something like 300ppm of CYA due to long-term trichlor use. Since then, I've had a beautiful pool and nothing has gone in it but liquid chlorine and acid.
I'm starting to have second thoughts, however. The cost to drain my pool was about $200 for 28,000 gallons. In other words, the cost of water is miniscule compared to what I spend on chlorine and acid...right now I'm running about $150/month in chemicals...a gallon of 10% chlorine every other day and a gallon of acid every 5-7 days. I live in phoenix and the pool gets used a lot by the dog, leading to a lot of aeration and acid demand. My TA is around 60 and my CYA around 50 as well.
Use of trichlor would remove some of the daily maintenance, as well as help to keep the ph down.
I'm wondering if it isn't much more cost efficient, not to mention more convenient, to switch it back to trichlor and do the math to keep the CYA in check by backwashing enough each week to remove a week's worth of CYA.
Has anyone crunched the numbers to determine if this is possible and/or cost efficient? Might have to bring up the CYA to a higher number to make the math work...