Pool problem

Hi

Could anyone help me please....I have an 8x4 pool and the problem is on the walls at the deep end there are lots ans lots oblack marks.

I have been to my pool shop and he said it was black algae, he said I need to brush the infected area with a wire brush and then vac the pool he then told to put algaecide in the pool, I did what he said and everything seem to be fine for about a week and then the algae came back even worse, the pool is using chlorene at an alarming rate and the ph keeps contantly dropping.

I can get the chlorine level up to 10ppm+ but the next i check it and it is down to 2ppm. I was told that when I vac'd the pool I should have vac'd to waste, because now the sand will be infected with the algae heads, wil this be true??

I could do with some good advice please.

Thank you all

 I had this problem with a pool i had in a house a few years ago.....i tried everything and it kept coming back.

I found out in the end that it was down to a water softener/purifier being fitted to the incoming water supply by the previous owners,this was reducing the PH levels.

It may be this....i gave the pool a chlorine shock and added algicide and that did shift it but as soon as the ph drops it came back.

Black marks on pool walls are usually algea, you will probabley get marks around the bottom of the walls and maybe on the bottom as well.

You maybe able to clear the marks short term by using lots of anti alg. and shock chlorine, but the only long term cure I have found is to regrout the tiles.

It is probable that the grout between the tiles is either gone or porous thus allowing the algea to grow and thrive.

I look after pools for friends while they are not here to help them out, three of the pools suffered from the same problem as you are having, one of the pools was regrouted last winter and is now a dream to look after.

Another problem you will have is having to use lots of expensive chemicals to keep the pool clean, algea eats the chlorine, once you have had you pool regrouted, your chemical useage will drop dramatically.

Your pool will look like new after it is regrouted.

Get some one in to quote your for a regrout.

Hi Georgina & mr.Kevin,

Georgina,

we too had a  water softener/purifier fitted but we decided we didnt like it so we took the filters out but left the casing, however we did the about 4 years ago...but you are also right, as soon as the ph drops the marks come back and no matter how much chlorine I put in the pool i never get a reading for longer than a day or two.

mr.kevin,

When I brush the algae from the walls there is clouds of white dust comes off have you any idea what this could be?

Thank you both for your replys.