Edit:oh wait...
rereads...
All purpose plant food?!?!
scrap the original post lol! pull the plants before they die!
Original post:
Wait! don't tear it down yet! get some black sand from petco or something and fill in the floramax. the flora max is likely not a good gap and allowing the ammonia to seep through.
to add the sand, first drain the tank completely
rinse sand well in a bucket, then take the sand and do a layer over the floramax. work your way around the plants. (assuming you have black? if not use whatever color sand your floramax is...)
cover everything with saran wrap, then fill. the saran wrap will prevent loose particles and dust from flying everywhere.
Allow the tank to run without livestock for a week or two. it WILL establish itself....do 50% water changes atleast once a week for the first few weeks...