Questions - Need some input

Earlier in the week I posted a request for an algae ID and i'm reaching out again for more help. I have been siphoning out algae for the last two weeks and it seems that although my problem has gotten better, it always seems to return just as quickly. Tested all of the water parameters and as far as I can tell the tank is testing within all parameters I tested.
Currently my tank is experiencing what I believe are nitrogen bubbles across the rockwork. While the tank has been running for ...

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