Tiny green black spot...worry?


Active member
Sep 15, 2010
South Mississippi
Ok...pools been looking good but seems to have lost a bit of that sparklypoolitus it once had. Can't quite put my finger on it .... But recently noticed a few tiny blackish green spots in the beach area(pebble area) rubbed & came off. Algae? Not sure if pool is quite as "bright" as was a few weeks ago. Could I have algae starting? Here's numbers as of yesterday. I know PH needs lowering-added acid immediately. Have never shocked-should I, for good measure?

Ph 8.0 (always high as I don't stay on top constantly-ugghh)
FC 4
CC 0
TA 70
CH 250
Cya 20 (added more stable)
Salt 3300
Temp 84


Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
Sebring, Florida
I would STRONGLY encourage you to get your pH below 8.0 and keep it there. Not doing so may bring you some unpleasantness sooner or later. :-D

How much more stabilizer did you add? What was your target?

There is almost no question in my mind you should shock your pool....if it's green/black and rubs off with your hand, there is about a 98% chance you have algae.


TFP Expert
LifeTime Supporter
May 30, 2007
South Carolina
Are you brushing your pool? What type brush are you using? How old is your pool?

Use a Nylon brush for vinyl, fiberglass, tile, and plaster that is less than one year. (Plaster includes any exposed aggregate and marcite finish, btw!) Combo brushes are for older plaster. All stainless are for algae (very stubborn green algae and also the ONLY brush for black algae.)

You CAN unscrew the Wall Whale from the nylon brush it comes with and screw it on a combo brush if your plaster is over a year old. Newer plaster is really too soft for anything other than a nylon brush.


Active member
Sep 15, 2010
South Mississippi
Added 20 oz stable....worried bout adding too much too soon as Im scared I'll over do it- target is 50.(that good?)
Pool is 1 1/2 yrs old. Regret to say ive not stayed on top of PH- add acid bout once a week & it's usually above 7.8 so I vow to do better! Will do OCLT tonight to see results. I have noticed some whitish spots in plaster- is that scale due to high PH? Haven't been brushing pool- how often should that be done once pool is back to normal? Thanks so much for all help! Guess pools are like kids...a little neglect early on has BAD consequences later on! (btw kids great!-Ha)