My pool pump 1.5 HP for 8,000 Baht, bought at a pump specialist - not a pool specialist - no problem over many years. Similar pump (or maybe the same with another name - Chinese product) I saw is now on sale separately also at GH, few sizes. Also their filter is OK - I am having over 15 years, working even after flooding.
Copper Sulfate can be bought at chemical shops for 150 Baht/kg sack.
My simple DIY equipment and the daily experience for my daily swimming throughout the year I have described in my post in Construction section, where actually this discussion belongs.
Also describing handling of my troubled source water (very strong ironized) what in all literature is as impossible for swimming pools.
Spending many hours studying what is available re pools, found so many rubbish, mostly with the hidden agenda (of the ones who run the show): buy what we advise you. Otherwise, our shops go bankrupt (with CS care and no pH care)...
Vacuuming - and backwashing - I cannot think to do it just once a month, especially when using the wonderful floculator/disinfector SaanSom. When seeing the outlet I am having onto garden (what obviously not everybody can see - direct somewhere into a sewage?), seeing after few days what's going out. Thru such a filth I should force my good water for one month long?