Quote Originally Posted by Waldog View Post
I am tempted to get some powdered shock and see if that will help?
You need to stop thinking of pool chemicals by their brands or descriptions, and start thinking of them by the chemical they contain. "Powdered shock" could be an excellent choice OR a terrible one, depending on which CHEMICAL is present in the "powdered shock" you have in mind. Neither we, nor you, know whether that product is good or bad for your pool, till we know what's actually in it.

Pool store operators and especially, pool chemical makers, really, really want to prevent you from getting involved "in the complications of pool chemicals and their effects": they want you to let them "make it easy for you". And honestly, if they actually did just that, PoolForum would be unnecessary. The problem is, they don't. The reasons are complex and pool store operators are themselves somewhat the victims of misinformation and misdirection from the pool chemical makers. But the bottom line is, the primary purpose of pool brands is to (a) sell you cheap chemicals expensively and (b) sell you rarely needed but high margin chemicals routinely.

Back to your pool: dusty debris on the bottom could be any of the following: mustard algae, dead algae (either green or mustard), sand from your filter, blown in or tracked in dirt or pollen.

You can probably rule some of these in or out yourself:
+ No dusty wind? Then, no blown-in dirt.
+ No pollen on flat surfaces outside? Then, no bulk pollen in pool.
+ No body tracking in dirt or sand? Then, no tracked-in dirt.
+ No yellowish-green somewhat uniform coating on your pool walls and floor, prior to accumulations of powder? Then, the dust is is not dead mustard algae.
+ Dirt does not feel gritty between your fingers, when you pinch a bit of it up? Then it's not sand.