Sediment

[belgique]

Problem: sediment settles on the bottom a few hours after vac (either to waste or recirc with some panty hose over the returns...can't see anything in the hose)
Comments:

• Water is sparking, perfectly clear
  I had a busted pipe in the sand filter 4 weeks ago so got a new insert and new sand. Filed the sand as per pool school. I'm positive nothing wrong there. I see nothing spurting out of the returns and the hoses don't reveal anything.
  Sediment is brownish. Do not get poofs of green when vac'ing...in fact it doesn't poof, at all.
  Our water does have a lot of iron in it but have not added much in a week or so.
  The sediment has stained the bottom of the pool in a lot of places. So, far can't get rid of them.
  I have lots of areas with a fine sandpaper like finish on the side. Difficult to impossible to scrape off.
  I just added 1 gal of muratic per the Calculator to get the TA down, and have the returns pointed up so I get surface action.
  I just added 2 gal of 12% chlorine per the Calculator to get it up to about 14.

What can I do to stop this sediment coming back...it happens within a couple of hours after vac so it cannot be growing that fast.

Once I stop that, how can I get rid of those stains? That's a lot of ascorbic acid

The numbers (before I added the aforementioned chlorine and acid):
FC 6
CC 1
PH 7.6
TA - Total Alkalinity 250
CH - Calcium Hard 275
CYA - 35

Thanks in advance! Steve

 

[Bama Rambler]

With a CC of 1 ppm it's most likely algae that's dying and falling to the bottom. You're killing it fast enough to keep from turning green but not fast enough to get rid of it. You most likely need to shock.

 

[belgique]

With a CC of 1 ppm it's most likely algae that's dying and falling to the bottom. You're killing it fast enough to keep from turning green but not fast enough to get rid of it. You most likely need to shock.

Well Bama, hat's off to you. I was leaning towards iron in the water. I had already brought it up to 15 and lo and behold this morning, there was very little sediment. I boosted it again at noon and brushed...very little there. And, that shock level has taken care of the stains on the bottom and sides that I had mentioned. Friend at the pool store (she knows I do BBB) says it is mustard...described the residue perfectly. So, I'll keep it at shock until it passes the over night test.

Many thanks for the help. Steve

 

[Bama Rambler]

I doubt it's mustard algae, but that doesn't change your plan of attack. Keep at it till you pass the OCLT.