I have a 75g tank about 2 years old, am using EI, 4 39w t5, co2, the tank did very well for about a year, then things slowed down, my J.blyxa stoped growing, i cheked and re cheked evry parameter seems fine, so i pulled it out vacumed few time, and same , will not grow and will not die, i added some root tab from ada still no improvment, went to 6 x39w not much of change.
more co2, fish not happy..........hmm
Then i pulled it out and removed 1in soil at that section of the tank, added new soil, wallaaaaa grow like crazy for 1-2 month then stoped . tried pumping evry thing up EI X2, nothing, again removed soil added new soil and things back again.
am dosing KNO3, PO4, TMG. GH booster, chalated fe, ..........
using lamote colormeter 2
things tests ok.......
had same problems with my 45g
now i wounder if the soil can support all these plants for a long time (i have power sand and about 3-4in AS ). You think adding fert to water colum is enough, but am not sure........