You could do a little DIY yeast co2, the algae won't much like that, but any co2 is beneficial to the plant, no matter the tech.
But right now, be patient. If one of your orchids gets scale, and you treat it, you have the bugs gone, but there is still problems that the plant is working out. The plant will eventually recover and fix the damage, no? Think of the algae as the scale, and the plant as your plants, but also your tank in general. The algae will go away when the tank is balancing itself.
"Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing it is stupid."
5g rimless journal
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