Algae or not!!

[firefly]

Hello everyone....new here and hoping to get some help..
Been reading the forums for the last 2 weeks and I still can't figure out why I still have black spots on bottom of pool..
I have a 21' AG pool with a sand filter...(about 4 years old)..and one of those nylon socks for the skimmer....been using chlorine capsules that I put in the skimmer and lasts about 2 days...
So after doing lots of reading....I went and tried the bleach method....poured 4 x 5 litre jugs of bleach in 3-4 days....1st jug I poured in the late evening....and then in the morning...some of the black spots seemed to have gone away and the pool seemed cleaner....then it rained overnight...and the black spots came back..(even more this time)...not knowing my cholrine levels....I added 2 full cups of granular chlorine and passed the robo-kleen vacuum...kids went swimming this afternoon and the pool was fairly clean....so tonight...come back home and the pool has the black spots again!!!!!
bought a 20$ test kit and these are my readings
chlorine-- 0
Alk-between 120-180 (done with test strip)
ph-- test strip indicates 7.8 and test kit about 8.0

The more I read...the more confused im getting!!!...I added 2 cups of chlorine this morning and a couple of hours later....test says I have no chlorine... :? :?

Please help

 

[pooladdict]

Hi Firefly and welcome to this forum.

I am sure you will get more information, but in case no one is reading this, this would be my simple minded suggestion, you have to do a chlorine check at nite, then one the next morning. If you have chlorine at nite, and back to 0 in morning, your chlorine is being used up by the algae in the pool, which could be your black spots.

Other then that, if chlorine levels are the same at nite and the next morning, it sounds to me like you have some metal problems perhaps.

Hang in there, try what I suggested and if that is the case, you need to get rid of that algae, and until you chlorine levels are the same at nite and morning.

Rik

 

[JasonLion]

We need a full set of test numbers, particuarly CYA, to really be able to help you. A good test kit is the best investment in your pool you can make.

 

[firefly]

thanks for the replies....sent an email to Dave to see if he can ship the test kits to canada...all I can find here is what they have at walmart or at the local pool store...so I bought the most expensive one( 20$) and I posted my test results
cl=0
Alk=120
ph=8

my test kit has 5 bottles but I dont see any indication as how to test for CYA.... :?

 

[The Mermaid Queen]

can you take a sample to a local pool store? (better than nothing!)

I would suspect that since you have been using the tableted chlorine, your CYA is pretty high, too high for the chlorine to be effective.

Get the test, and post back.

 

[Wolfmarsh]

The fact that your chlorine keeps going to zero means that something is using it up.

You need to do like everyone else said and get some test numbers asap so you can know how much chlorine you need to add to get it to shock level.

 

[firefly]

well I will be ordering a Taylor test kit and will post my readings shortly....

 

[frustratedpoolmom]

Sounds like good ol' black algea....pour a couple of jugs in the pool while you wait for your kit