I have an 18,500 gallon saltwater pool that is very dark green. It was green and I put chlorine in it and I watched it turn even darker. I had my water tested and there was no copper in the water. My Cyanuric Acid level is at 94, my Total and Free chlorine levels are at 1, my pH level is at 7.5, my Total Alkalinity is at 105. My total Hardness is at 82, my Minerals level is at 2500 and the Borates level is at 31. The list of products recommended for me are as followed: 93lbs of Mineral Springs Beginnings, 1lb of Balance Pak 100, 0.25lbs of Lo ‘N Slo, and 24.25lbs of Balance Pak 300. I am afraid to put anything in because last time when I put some shock in the pool it turned an extremely dark colored green. I cannot see to the bottom at all, or even the ground in the shallow end. I am extremely frustrated and have been dealing with this problem since I opened the pool in May. I was hoping you would have some solutions or could possibly offer any sort of advice. Thank you. Kayla Mayo (kaylamayo007@aim.com)

Question:

I have an 18,500 gallon saltwater pool that is very dark green. It was green and I put chlorine in it and I watched it turn even darker. I had my water tested and there was no copper in the water. My Cyanuric Acid level is at 94, my Total and Free chlorine levels are at 1, my pH level is at 7.5, my Total Alkalinity is at 105. My total Hardness is at 82, my Minerals level is at 2500 and the Borates level is at 31. The list of products recommended for me are as followed: 93lbs of Mineral Springs Beginnings, 1lb of Balance Pak 100, 0.25lbs of Lo ‘N Slo, and 24.25lbs of Balance Pak 300. I am afraid to put anything in because last time when I put some shock in the pool it turned an extremely dark colored green. I cannot see to the bottom at all, or even the ground in the shallow end. I am extremely frustrated and have been dealing with this problem since I opened the pool in May. I was hoping you would have some solutions or could possibly offer any sort of advice.
Thank you.
Kayla Mayo (kaylamayo007@aim.com)

Answer:

The hardness is a little low, so I assume one of the chemicals recommended is addressing that. The salt level (2500) may also be a little low so there could be a significant amount of salt (sodium chloride) that needs to be added, the ideal level depends on the salt generator manufacturer's recommendation. Otherwise, the dark green could be metals, even if the metal test shows 0. Why? Because now the metals that are in your pool are precipitated out (dark green particulate) and therefore they are not dissolved in the water and may not react to the test. I would still recommend adding a metal/stain remover if the chlorine intensified the coloration upon addition. Likely this is due the the oxidation that the chlorine caused of the chemical.