I'm thinking maybe recheck the CYA to see if your not borderline 50 and the slam isn't high enough.
Iowa Vinyl Pool
- Thread starter Snoobug
- Start date
BigPapaSmurf
Well-known member
That is what I did at my parents pool, when they had this issue. I used a brand new toilet brush and good rubber glove. I pour the bleach directly on the brush and gave it a good scrubbing, then I added some more bleach and let it sit for about an hour. It does look like black algae.
With no suction it will ‘float’ in the up position.
*also why the water level needs to be about half way up the skimmer opening. If it’s too high the styrofoam piece at the top of the door won’t let it fall to let water/debris in, even with the pump running.
*also why the water level needs to be about half way up the skimmer opening. If it’s too high the styrofoam piece at the top of the door won’t let it fall to let water/debris in, even with the pump running.
Shut off pump first. Block the weir door closed pull basket out and temporarily put in a rubber plug, scoop out some water and then add bleach/ chlorine.brush as you wish but keep the mixture in the for a bit to sanitize your skimmer area. Put the basket back in to sit in the mix.
I wish I had long gloves, all I have are nitrile ones that go down to the wrist... I will have to look to see if I have an unused scrubber brush...
Just checked it, put in more LC and scrubbed again for good measure, letting the skimmer basket soak...
- May 3, 2014
- 62,727
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Looks like sunscreen, hair products, etc. Put a tennis ball in the skimmer.
Just checked the skimmer, looks good. Pump is back on! Searching the house for a tennis ball... 
Update: they are in the garage.
Update: they are in the garage.
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Does the tennis ball fit the category of "chuck and replace" or "rinse and reuse"?
I bought new ones every year and rinsed them anytime I felt the need. 3 were in the pool at all times and 3 more would join them for parties. They mostly lived in the skimmers.
Thanks. Ordered some more. That black line reappeared... I scrubbed it. Annoying.
- May 7, 2014
- 429
- Pool Size
- 29980
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
I have been buying scum balls for my hot tub and have thought about getting them for the pool. Never considered using a tennis ball. @Snoobug I get black in my skimmers at the waterline too, but it does not look like yours, mine looks like smeared grease and is dry to touch. Mine is just body/suntan oil, it wipes out easily with a Clorox wipe and takes weeks/months to come back.
I keep scrubbing the skimmer... it grows quickly. I may do another LC Skimmer Bath...
Try using straight chlorine on a brush to give it the quick kill. Be careful.
I'll turn off the pump again. I'm going to put a trash bag around my arm and scrub...