I have something growing in my pool

1.      Determine what it is.

          1.1     It is floating free in the water.

                     1.1.1  Slightly green - How to treat a Green Pool

                     1.1.2  Green, can’t see main drain - How to Treat a Green & Cloudy Pool

                     1.1.3  Dark Green, Can't see bottom step! - How to treat a Dark Green Pool

                      1.1.4   Swamp water (Black - Zero visibility) - How to treat a Swamp

          1.2     It is on the walls, floors, or surfaces of the pool or spa. Determine if it is algae or stain.

                     1.2.1  Does the discoloration scape, scratch or brush off? Algae slime will also stain the surfaces if left on them, but black algae will grow in colonies that come off in scrapes, Mustard and Green slime can brush off clouds when scrubbed.

                     1.2.2  Does it look like sand or dirt, and keep coming back to the same spot on the wall (for instance). Chlorine hard to keep up? Mustard Algae most likely

                     1.2.3  Is the pool source water, well water? If yes, is the stain over the whole pool? Treat with stain preventer, recommend changing water source if possible.

                     1.2.4  Is the pool vinyl, and the ‘stains’ black or almost black. Mildew from beneath the vinyl. Refer to a vinyl specialist, usually needs replacement, with mildew treatment of the soil underneath

                     1.2.5  Rust coloration around return fittings. Good indication of heater online that has lost the coating on the iron heat exchanger, disintegrating from poor chemistry, low alkalinity levels.

                     1.2.6  Blue / Green marbling on walls and surfaces. Don’t let any blondes go swimming! Green hair is caused from the presence of copper in the water for the chlorine to stain the hair green! Blue pigment (on the walls) is copper, usually from algaecide or copper components disintegrating from poor chemistry, low alkalinity levels. Treat with stain preventer

                     1.2.7  Gray marbling, usually due to Silver in water, source is usually algaecide, possible ionizer problem

                     1.2.8  Large brown stains, usually caused from leaves or tree sap. Maganese, treat with stain preventer

                     1.2.9  Brown speckles, usually fertilizer, treat with stain preventer.

                      1.2.10    Blackish Purple color across the floor, maybe up the wall - caused by Acid, Chlorine, Calcium (in the plaster) reaction. Acid was added at high chlorine or Chlorine was added at low pH. Will occasionally disappear after several months, possible spot acid washing only resolution.