Do I Have Brown Dirt Or Is It Brown Algae?
I keep getting what looks like real fine brown dirt that settles on the bottle of my pool.
I spent several hours vaccuming just the shallow end yesterday only to fine the same brown mess this morning.
I had even cleaned my cartridge filter immediately after vacuuming. It appears that as soon as I take the vacuum system out, it shoots everything I just sucked out back into the pool.
This isn't the first time.
It has already happened several times since early April.
My builder said it sounded like pollen.
I don't think so.
Today, I had a guy at Leslie's Pool supply tell me it was brown algae and to use a copper based algaecide.
Thanks for the question Donna
Your problem could be dirt, so before we start adding all kinds of chemicals, let's take a look at what you do and your filtration system.
The question says you have a cartridge filter, which I highly recommend. Let's say your cartridges are fairly new, without any tears or rips, and you keep them cleaned out. Once per month for normal usage is good.
The skimmers are kept clean and you clean the pump basket as well.
All the chemical readings are good. You keep your chlorine level between 1.5 - 3.5ppm.
The question does say that after you vacuum the "dirt" comes right back into the pool. This could be a torn or ripped pleat
on the cartridge.
But, if the pool looks good, and after a while, maybe overnight, the brown dirt reappears in the same spot, then you probably have brown algae.
Now the pool guy said to use a copper algaecide, probably chelated copper. One of the big concerns for this kind of algaecide is that it sometimes produces what's called "pool goo" or "pool tar" in vinyl swimming pools.
Unfortunately, your pool guy may have been mistaken. Any algaecide, regardless of its use, is for preventative maintenance, not to get rid of existing algae.
It's an insurance policy, nothing else.
The only way to get rid of algae, whether it's brown, green, or whatever, is to give your pool a good chlorine shock and a little manual labor.
If you keep your pool chemicals perfect, but still have a brown algae problem, I would recommend a PolyQuat 60 algaecide. This doesn't have any metals and will work for your issue.
After you add PolyQuat, you free chlorine level will drop. You'll need to add chlorine a day or two after.
Remember to test once, if not twice, per week during the Summer for all your chemicals.
I recommend using a Taylor FAS-DPD K-2006 pool test kit. The best on the market and the one most pool professional use.
Water Testing Kit
Pool Water Testing
Hope this clears it up for you. Have a great and safe swimming season.