Black Stains All around Wall of Vinyl Pool Long Beach NY

[jml475]

I have a 16x32 Vinyl pool approx 18000 Gallon Salt Generator. When i opened the pool it had dirt a leaves at bottom and pool was green shock and filtering cleared the pool up in a couple of days. But I have blackish green stain all a\the bottom 1.5 foot of the wall of the pool completly the floor is not stained at all. When i put a vitimin c tablet on it it did nothing but with a piece of chlorine it worked. What suggestion to get rid of the stain.
An additional problem I have is High hardness level I dropped 50% of the pool and it is still high any suggestions.

 

[Bama Rambler]

My first suggestion is to post a full set of test results and how you got them.

Holding the FC at the high side of normal will lighten the stains.

 

[jml475]

FC 1.0 PH 7.2 TA 80 CA 50 I ran out of my test solution for hardness but my strip test indicates its near 1000 water is clear.
I emptied 50% of the pool and did not seem to have much of an effect on total Hardness . So your suggestion is to keep FC at around 3 and the stain should lighten? What should I do about the hardness issue? I tested my tap water with a strip and it indicates very low. Should I dump more water?

 

[linen]

Welcome to tfp, jml475

Should I dump more water?

Not yet. The strips are your first problem...the results they give are wrong more than they are right. So first you need to get an appropriate test kit. See: http://www.troublefreepool.com/pool-school/pool_test_kit_comparison Many of us on here like the tf-100 since it is the best value.

 

[jblizzle]

Welcome to TFP!!!

Please read Pool School and learn about the chemistry.

According to this FC/CYA chart, for a CYA of 50ppm (that is what you meant by CA right?) the MINIMUM FC level that you should ever allow is 4ppm. Bama suggestions was to hold it up around 6-8ppm to lighten organic staining.

Why dump more water when you can not accurately test yet?

Which kit do you have? Is it one of the Recommended Test Kits?

 

[jml475]

I have a no name kit I picked up at a local pool shop. I will order the TF-100 as suggested. I will increase my FC level as suggested and wait until I get a more accurate reading on harndess before I dump more water. Thanks for your help I will keep you posted.