New Problem After Calcification Issue Was Supposedly Resolved

[poolcare novice]

A technician from the local pool supply chain determined calcification clogged the pump & caused it to shut down. The best solution was to partially drain the pool to hopefully lower TDS and Calcium Hardness. My strip test of fill water showed the TDS to be 0 and the Calcium Hardness to be 250. Here is a summary and the bad news as of yesterday.

Here are the test results from the same local pool supply chain.
Before the partial drain (no mention of testing for Nitrates)-
FAC: 2
TAC: 2
CA hardness: 1,000
CYA: 120
TA: 200
pH: 7.6
Copper: 0
Iron: 0
TDS: 4,500
Pho: 1,500

12 days later. After the partial refill and filter clean (once again, no mention of testing for Nitrates)-
FAC: 1
TAC: 1
CA hardness: 1,000
CYA: 120
TA: 160
pH: 7.6
Copper: 0
Iron: 0
TDS: 2,200
Pho: 1,500
Temp: 65

13 days later at a different location of the same chain. After adding 257 oz. of Muriatic Acid (14.5% HCL) 1 qt. 13 oz. at a time as recommended by the store to reduce TA and not seeing much of a reduction with my strip tests. (This time the salesperson told me she would test for Nitrates). She said the Nitrates were 120ppm and I must drain and refill again. She said fertilizer or fumigation would be the cause. I told her the neighbors fumigated their entire house recently and she said that ruined my pool.

FAC: 3
TAC: 3
CA hardness: 1,000
CYA: 200
TA: 150
pH: 7.8
Acid Demand: 2
Copper: 0
Iron: 0
TDS: 2,600
Pho: 300

Am I forced to completely drain and refill? Thanks.

volume is actually 28,000 gallon (estimated by pool supply store) in-ground concete

Edited February 9, 2016 by poolcare novice

[chem geek]

How did your CYA jump from 120 ppm to 200 ppm? Obviously the test results you are getting from different pool stores is inconsistent. Also, you should not be using test strips if you want to have accurate readings. Get yourself a Taylor K-2006 or a TF-100 test kit. These are accurate drop-based kits that should give you consistent results.

If your TA is high, that can be lowered with a combination of acid addition and aeration of the water, but if your CH and/or CYA are high, they require water dilution to get lower. It is the combination of pH, CH and TA that are the main factors over-saturating the water with calcium carbonate. While some people do manage their pools with a CH of 1000 by keeping the pH and TA lower, your high CH fill water will increase CH over time with evaporation and refill so you might as well do a partial drain/refill to lower the CH and the CYA.