If you see this small, fingernail-sized aquatic insect in your pool, most likely your Free Chlorine (FC) level is too low for your current Cyanuric Acid (CYA/stabilizer/conditioner) level.
I consider them nature's very last warning before your pool is overridden by a full blown algae bloom. Their presence suggests that it is no longer safe to swim in your pool before increasing the FC to the correct level, letting it circulate for 20-30 minutes, then retesting to make sure you successfully achieved the correct FC level.
How to get rid of them and prevent/keep them from coming back:
Achieving and maintaining proper chlorination/sanitation will resolve this issue, no special chemicals will be required and you do not need to capture/remove them. You can expect them to disappear a few hours to a day after achieving the proper FC level.
Even though they swim quite well, you can capture and remove them with a manual pool skimmer on a pole if you want them out of your pool sooner.
These Pool School Pages will help you understand how to achieve proper chlorination/sanitation in your pool:
ABCs of Pool Water Chemistry
How to chlorinate your pool
[FC/CYA][/FC/CYA]
PoolMath
PoolMath Tutorial
Extended Test Kit Instructions
Videos of the tests
SLAM Process
Need a test kit?
https://www.troublefreepool.com/content/124-pool-test-kits-comparison
If you need a test kit that tests for FC, CYA, and the rest: http://tftestkits.net sells the wonderful TF-100 test kit, ideal for practicing TFP pool care. Their custom test kit is a fantastic value, uses fresh, official, and industry leading Taylor testing chemicals, and their company provides perfect customer service (owner is active TFP member too). Behind that humble website is an awesome company I am proud to buy from. Investing in a test kit and doing testing yourself can help you save a lot of time and money on pool care.
To help others find this thread:
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