First thing, stop feeding them! You’re using FFOF. It takes about 4-6 weeks to deplete the soil nutrients.
Give them NOTHING but water until then.
Since you’ve overfed them…you need to flush the soil ASAP. That means, water them (with just water) until a bunch of water comes out the bottom. Then just let them be…let the soil dry up (about 3 days). Then continue to use just water.
Please follow my post…as all the questions you have are already answered.
Good luck!