I see you are dosing AFR. As @drexel stated nutrients are seldom used up in a 1-1 ratio. I use AFR in my nano tank. I originally began dosing it just based on DKH as per the instructions. After about 2 months of dosing I noticed that my calcium had gone through the roof(590ppm ~). After doing some internet searches I came across an interview with Lou from Tropic Marin(RIP Lou). In this interview he had mentioned that he had the same issue and had found for him it worked better for him to dose the AFR based off of his CA levels and supplement DKH if needed. His reason for this being that if your tank has any detritus build up anywhere then, over time, as this detritus decays and releases acids into the water, the alkalinity consumption will go up disproportionately to the calcium. The other side of the scale is in tanks that have more macro algae (be it nuisance algae or refugia) can disproportionately absorb calcium.
So in short he was saying without saying that their product only works perfectly in a perfect tank scenario. As such he essentially was still dosing a sort of 2 part even though AFR claims to be an all in one.
Hope this helps you out with your AFR dosing.
I also hope you do figure out the issue with your mushrooms. I had a time when my mushrooms weren't doing so well either and lost quite a few. I know how frustrating it can be. I wound up just giving up on them for a while then the few I still had for no reason that I can recall just bounced back and are thriving again.