Hi all. So I discovered this site 2 years ago (have had a pool for about 5 years) and did a lot of reading (but no posting) and learned so much. I have been using pool school and pool math ever since then to keep our pool in pretty decent shape. Here is my current situation:
We have a big rust stain in our shallow end that has been there since we bought the house. A couple of years ago the pool was drained to replace the tile and coping and we had them try to see if they could etch it out if it was a surface stain. Unfortunately it is clearly coming from within the pool so it actually looked worse after that. We realize the real solution is to cut in and fix the problem from underneath (probably rebar causing it). Our plaster is old and will need to be refinished soon and we will fix this at that time. In the meantime….I researched on here and decided to see if I could improve the appearance of this with the ascorbic acid treatment. Especially since last year I noticed more staining on our walls that I thought might be caused by this.
I did the treatment with ascorbic acid in a sock over the area plus spread around sides of pool. Definite improvement. The main stain is still there but the surrounding areas where it had "spread" are totally gone. My mistake was (I think) that I didn't add sequestrant fast enough. There was a good full day that passed before I managed to get some. Now the stain is still better but I feel like there are stains along walls in other areas of my pool. So my question is - do I need to repeat the whole ascorbic acid treatment now or can I just add more sequestrant to fix this?
Also, how long do we have to wait to swim after adding either ascorbic acid or sequestrant? I added the ascorbic acid about a week ago and have had trouble keeping chlorine in the pool ever since starting to bring it back up but have stayed on top of it as best as I can - testing and adding twice a day. I think from what I've read that this is normal but just wanted to make sure? We swam yesterday after I had made sure chlorine levels and pH were ok but now if I need to add more how long do I need to wait again? AND, we JUST added a gas heater to our pool that was up and running two days ago. pH has been right at 7.2 (per instructions), do I need to start bringing it up more? I definitely don't want to damage the new heater. I'm starting to feel a little in over my head as I don't know what the best thing to do from here is. Any advice would be greatly appreciated! Since I'll probably be asked, here are current parameters (from Taylor K-2006):
FC: 0.2 (already added more based on pool math)
CH: 200 (started at 100 this season and have been adding to bring up)