Ok, now that I have your attention with that subject line you're probably going to say: NOOOO, don't do it! And I 100% agree and have learned here about the dangers of high calcium with CalHypo and high CYA with Trichlor but this is I'm afraid might be my only option. And to reiterate - this isn't my pool either (Iím working on getting one built soon for my own home, that's why I've been here to learn) so here's some back story:
Went to visit my parents last week who are in their 80's. They have a plaster IGP, about 14k gallons with DE filter. Back 20 years ago when I lived at home I used to take care of the pool maintenance for them. I used liquid chlorine exclusively to chlorinate. Since I moved out some 15 years ago they had a pool service that would come weekly then decided after about 10 years of that they could not afford spending money on the pool anymore so they stopped the pool service and started using a floater and Trichlor pucks. Of course pool was overrun with algae after a while of that. When I would come to visit I would ask about the chemicals and they would say: "if it were up to us we would just fill it(pool) in with dirt". But they can't afford that option either. Anything besides adding pucks to a floater and testing for PH once every few weeks(which for him is dropping Phenol reagent drops on the surface and watching if the red color turns or not as it floats away) and adding a little MA once in a while my dad will not partake in ANY more maintenance than that. They cannot afford a SWCG and I cannot afford to start dumping money into their pool equipment either and I am too far from them to offer any help with the maintenance and can only get up there once a month at most. Last time I was there a few weeks back the pump wasn't running (they decided it was too expensive to run it the 2-3 hours a day I had them cut down to) and of course without any circulation the algae was so bad there were backswimmers everywhere. Even if I had my test kit I would have been afraid to dip my arm in just to get a sample filled.
So here's my plan:
Test water next time I'm there. Knowing beforehand the CYA will be off the charts since they have been on Trichlor tabs exclusively for the past few years so will most likely have to drain half the pool off. So after I go through the shock process and get the water clear again I need to get them on some kind of 'minimal' pool maintenance program.
So here's my plan for a that:
After clear from the shock process and all levels are within spec, get them to 50ppm borates. (This will cost me ~$50 or so with 10 boxes of Borax and 3 gallons of MA but I can swing that) I feel this hopefully will buy some more time until I have to do a partial drain from over CYA levels which will be inevitable running the Trichlor pucks. I'm hoping the borates will supplement the pucks to stave off algae until the CYA level gets too high to render the chlorine level with pucks useless. Once the CYA gets too high which I think would be around 6 months(?) I would do a half drain and re balance the water. So besides my dad buying the Trichlor (I might have to buy these as well), making sure the floater has pucks, checking the PH (he doesn't understand any other chemical tests than that and doesn't want to know) and he is running the pump for the 2-3 hours a day (I tried longer and he refuses) this would be most maintenance I think they can handle for their pool along with as much as I can assist visiting once every 4-5 weeks running all the other tests. Or maybe instead of Trichlor pucks, use Cal Hypo pucks instead? My concern with that is now the CYA level will be fine but with raising calcium levels, will there be scaling before I can do a partial drain every 6 months? If not then this solution would allow me more FC from decent CYA levels to stave off Algae but if at the expense of scaling, I'll take algae instead.
So, my question with this is: is this possible in theory? If this is not possible to keep the algae away for at least the 6 months then what would be an estimated timeline? More like 4-6 weeks instead? I figure if algae returns then I can shock to rid the pool but going through a shock routine every 4-6 weeks would be too expensive for me to handle. Also, a partial drain and refill will cost my parents too much money in water costs if itís any more than 6 months so they wouldn't go for that either. Talking them into a 6 months drain schedule will be hard enough as they would not even begin to understand the high CYA problem and why the pucks arenít working. We are in SoCal so there is no off season for pools, sun is always making it's rounds here so besides winter which does get the water temp down some, the sun is feeding the organics in the pool most all year round. I thought maybe about a Stenner pump to chlorinate but that would require them buying the liquid chlorine often anyways which they don't want to do and to make sure the chlorine supply to the pump is maintained, and then the cost of running that pump would be questioned....