Ron,

I'd suggest another approach, different than N.Wise's :-)

Drive the N and P down to rock bottom zero - by say doing two 80%
water changes back to back and ease up on the fish feeding. Keep them
at zero for a week.

During that time continue normal the Fe/trace additions. Make sure
your CO2 is indeed 20 - 40 (time to double check your pH and KH test
kit or digital monitor).

Just another approach.

--Nikolay