Black algae

To confirm that it is black algae, scrape a bit up and smear it on a white piece of paper. Black algae will smear green.

We'll need some additional info to be able to help.

1. What kind of pool is it? What is the volume?
2. What size pump and what kind and size of filter?
3. Exactly what all have you added to the pool, meaning ingredients and not just product names like 'shock' or 'algaecide.'
4. What does the water look like?
5. Do you have a drops-based test kit? If so, what kind? Post current numbers.

If you don't have a good drops-based test kit:
The test kit that we think is by far the best is the Taylor K2006 or 2006C (better buy). Not available locally but you can get it through this link that takes you to Amazon: http://pool9.net/tk/ You'll need this kit to be able to measure the high chlorine levels you will need to be able to eradicate your pool of algae. Other test kits can only measure to 5ppm which is not gonna do it.

Until you can order and get the K2006, go to Walmart and see if they have the HTH 6-Way drops-based kit (no test strips!) and get that. If they don't, get an OTO/Phenol Red kit (yellow and red drops) instead. Use it to test and then post your numbers. Also while you are at WallyWorld, get several jugs of their generic 8.25% bleach and a couple of boxes of 20 Mule Team Borax (laundry aisle) and a gallon of distilled water.

Repost with requested info and then someone here can try and help you.

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