Hello all. I have had a pool for a while but this is my first forum post. I am in France and I rent out my house to English families over the summer, usually for one or two week rents totalling about 12 - 15 weeks per season. During the season I live nearby and I check the pool every morning, usually before the guests wake up to give them as much privacy as possible. Saturday is changeover day when the guests leave at 10am and the next group arrive at 4pm. There's a lot to do on Saturdays but the first job is always to vacuum the pool so that it looks perfect for the arriving guests.
To be honest, the pool has been a constant worry and I have never really felt on top of it. The house can take up to 12 people and there are often lots of kids. There is a shower next to the pool and I ask people to use it, but I know that most people don't. They are on holiday, they have paid a lot of money to be here, and they will darned well do as they please. One time I was here and watched as two girls plastered themselves with suntan lotion and then jumped straight in the pool. Sometimes there is a ton of beach sand in there, sometimes soil and debris from the garden. Guests vary, of course, but some of them can certainly give the pool a pretty hard time and there is nothing I can do about it.
Luckily, the guests don't seem to notice, or don't care, if the water is a bit cloudy, so by the skin of my teeth, I have always managed to survive. It always baffled me why I found it so hard to keep the water clear. Surely this kind of usage is nothing for a commercial pool? Obviously, I was missing something big, and reading this site, I'm sure I have found it…
The only chlorine sold for pools here is trichlor pucks. There are no pool shops near here but the supermarkets are stacked up to the rafters with more kinds of trichlor pucks than croissants … not to mention flocculants and anti-algae stuff by the pallet load. For testing, what they have here are those crappy blue box kits with OTO and phenol red. And as you know, the most common advice you find everywhere is to maintain FC at 1 - 3... Well, you can just imagine…
My routine in the past was to have the SWG set to maintain FC at 3, and then each morning I would check it and if the FC was down or the water looked a bit cloudy I would add fast pucks to the skimmer to bring FC up quickly before the guests got up. Like I said, I got by, but you don't need to tell me it was a crappy way of doing things. I simply didn't understand the FC/CYA relationship.
After spending several days studying this wonderful site, I have (literally) chucked out the 700 page book I bought, and I feel much more confident about the future. My CYA was at 150 so last week I drained and replaced almost half the water. CYA is now 94, but guests tend to splash a lot and I backwash between guests so it should come down to target within a few weeks. Today, the pool is crystal clear and the numbers are:
After a determined search I have found a source of 9.6% bleach - in a local garden shop, of all places, so I will not be using pucks ever again. I will use your recommended SWG levels but I guess my FC needs to be up around 9 until the CYA comes down to target? Does that sound ok, or would you suggest an even higher FC? I saw somewhere here that 20% FC/CYA would be appropriate for a commercial pool. Would you recommend that in my case?
By the way, the water will be between about 80°F and 90°F most of the time, and I run the pump 8 hours per 24 hours when guests are here. Does that sound about right?
Any advice will be very very very gratefully received!