That’s green hair algae. You can scrape it off with a toothbrush or use excel.
I haven't had good luck scraping it off plant leaves.
Any strategies you've used?
You can pull it off with your hand while you have your gravel siphon to suck it up.
You can also use liquid carbon like Excel. It’s basically an algaecide, it can easily kill hair algae. If you have plants like vals or anacharis, it might cause them to melt.
Excel just arrived from Amazon. How much do you recommend and how often? (20g tall)
I would do half of what is recommended. I see you have shrimp, they are quite sensitive. Continue for a few days. You can also get a plastic syringe and squeeze it close to the algae.
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