Sorry.
Against my own policy, I started to answer your question . . . and immediately ran aground on the problems we have always faced trying to help non-US pool owners:
- It's no use for me to ask what pump you have . . . since I wouldn't know it.
- It's no use to tell you which kit to get, because you probably can't buy it.
- I can't tell you what chemicals to use . . . because I don't know what you can buy.
You might try TroubleFreePool.com. I'm pretty sure they still accept international questions, and they might have someone onboard who knows what works in Mexico.
Sorry!
Bookmarks