Brown Stains In Pool Quickly Getting Worse

tpreva

New member
Apr 30, 2025
1
USA
Hey All! New to the forums but have been lurking for a few months due to a new to me pool.

Opened it 2 weeks ago and it has been a bit of a nightmare but finally felt like I was getting somewhere when brown spots started appearing everywhere. Think it is Iron but looking to get some help.

Current reading in pictures with high FC due to slam process.


Pool Backstory-
Bought house with a fiberglass pool a few months back. Opened the pool to a swamp that we quickly cleaned, but after testing the pool showed mostly 0s across the board with Taylor liquid kits. Was confused but after multiple times testing found out there was almost no salt, FC, or CYA. Brought all 3 up to level over the last weeks and the water cleared up but now the bottom of the pool is speckled with brown spots. Not sure of what to do as they will not come off with scrubbing and only get worse every day. IMG_5962.jpegIMG_5960.jpeg
IMG_5954.jpeg
 
Did you fertilize recently by chance? It does look like Iron to me as well, but check out this article especially the Vitamin C test to test for Iron stains.