brown stain

Well, first time poster... go easy. Hope this is the right thread. So here is goes: We have a 45qm salt water pool, its in Northern Spain, and is operating all year round. The pool is tiled and has had a full re-tile 10 months ago. At that time it was also changed from chlorinated to saltwater...

Recently ended up replacing a spa light bulb, as soon as I unscrewed the light case from the wall, there flew out a bulk of dark rusty stuff from the hole. I ended up scrubbing it off with brush, which clears up the stain, but as soon as I run the pump/add chlorine, stain comes back. It's the...

Hello Fellow Pool Boys and Girls, We just finished building our pool about a month ago. Unfortunately, we've developed a pea sized spot with a black center and brownish cloud moving away from the center. I tried placing a chlorine tab on the spot, for approximately a week, and brushed...

When I opened my pool this summer, my spa ( where the water had been lowered and 2 pillows used to support the cover, had a brown stain above the water level. I thought it was organic but after many shocks, the stain remains. Also found a little brown stain at spa light. Other than that, the...