The parameters will most likely read 0 from a bloom like that.
Algae feeds off of nitrates and phosphates in the water column. Do water changes with ro
water, reduce feeding, rinse food if frozen, and manually remove algae during water changes.
Algae battles are usually long when tying to get things in check. Just keep with it. There are also 2 articles in my signature that discusses battling algae you can read through.
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