Again, you are going through what I have gone through, including traveling as I used to travel Sun / Mon - Thu / Fri almost every week in the past. I was mostly worried about the water level (evaporation or a major rain storm) as chemicals can be balances later.
If not already, get one of those apps such as Pool Pal, Pool Math, etc which does help with the amount of chemicals.
Luckily, we do have a pool store (but 30 mins away while Walmart is less than 10, and Leslie's around 20) and I pick up 2-3 5 gallon jugs of 12.5% chlorine time-to-time.
As for the algae "dust," I try to brush often and sometimes (when I am lazy), I shut all the valves except for the main and try to have the main suck up as much dust as possible.
Good to know that you can see things from my perspective, have gone through a similar situation. Hopefully, my frequent need to travel will end at some point this year.
Last two or three days, I tried to dedicate mostly to that pool issue. All in all, I bought 24 gallons of 12.5% liquid chlorine (two batches of 12 gallons, each). Two days ago, I added 8 gallons at once during the evening. Following up, added 3 gallons in the morning of the next day, one more in the afternoon. Bought more chlorine late afternoon and kept on adding it throughout the evening. And yesterday night, added more 8 gallons. Also, I brushed the walls and the floor yesterday night and the day before. Pump was running all the time. No much in terms results there, an almost abysmal failure.
When the pool was nasty green with algae bloom and whatnot. Superchlorinating and more chlorine (two gallons the next day morning) had great effect -- it went from nasty and murky green with algae bloom to a nice blue (however cloudy the water still was).
Largely, it was my fault. Since I knew that the CYA was very high, at about 75ppm; or, at least, that seems likely the reason. I am crunching for time and have to travel tomorrow, and will be away for about 10 days and thus was trying to get that thing done once for all (in hindsight it was a stupid move).
Reason for what the CYA was so high? At first (about 2 months ago), the CYA was very low (measured using Taylors kit [could see the dot no much what]. I read about the subject in more than one source, and knew that one should use skimmer socks in order deploy the CYA. Ordered the socks online and bought few 1lbs CYA bags just in case (also, it had a good price at the time). The socks took several days to arrive and while reading the instructions that came on the CYA packaging, it was noted that it simply did not mention the need for socks or anything of the sorts; so, I assumed in that for this particular CYA brand (due to size of the pellets or chemistry), the use of the socks weren’t required – after all, the manufacturer (or supplier) of that particular product should know better.
By adding the CYA directly to the skimmer with no socks, it seems that most of the CYA got stuck at the sand filter instead of affecting the water which then made me believe that the CYA in the water was extremely low, given that adding few pounds of CYA did not even make a dent. Given that the CYA seemed so low, it made no sense to waste so much of the test kit testing it all the time. End result, CYA likely was released from the sand filter slow, and now it very high. The deal now is to slowly deplete the water of the pool and replace it with new water. But, CYA should wear off over time.
In any case, have to travel tomorrow and will be away for about ten days. So, I went ahead and did perform the slam anyways (with high CYA). Could have lower the pool water and add more water to replenish it, but that on itself posed another problem: to where I am going to dump all that water? Even though the drain is pointing to my front yard, lots of water bleeds to the sidewalk and the curb in the street by simply backwashing the sand filter for 2 minutes and rinsing it for 30 seconds.
I believe that the high level of CYA rendered the chlorine much less effective. There has been some improvement though, I can see the floor/bottom of the of pool on its shallow end – not on its deep end or in-between.
Today morning (around 9am) I added the last two gallons of liquid chlorine to the pool. Not sure if it is worth buything more given the circumtances.
Also bought two gallons of chlorox algaecide+clarifier. It seems to be ok to use when the pool is superchlorinated, but wouldn't the high level of CYA render it less effective as well?
On another thing… often, when I brush the deep end of the pool the pressure gauge on the sand filter goes down substancially – from 19PSI to 13 or 14PSI. And afterwards, often, the pressure stays at 13, 14 or 15PSI for several hours. Ironically, if I backwash it the pressure often goes back to 19PSI short afterwards.
Thanks!
