Welcome pdancosse
You are right in the middle of cycling your tank. A good thing for the future health of your tank, bad news for the fish
Adding prime at this point will do nothing for you except slow the process down by giving them few hours of relief. Nitrites will continue to be measurable until the bacteria colonies become fully efficient.
Read the sticky on tank cycling in the freshwater forum. The stress you are feeling is the reason most experienced hobbyist recommend Fishless cycling.
Sounds like the Bio Spira was alive and well ( it is extremely perishable), it is the only product known to experienced folks that really works. It will help speed up the cycle.
Nitrites are extremely toxic to fish, short of moving them to a safe tank, a lot of damage has probably been done and cannot be prevented. You could raise the salt level in the tank 1/2 tsp. per 5 gallons. This would help your fish with the stress associated with nitrite poisoning, it will not detox the nitrite.
Hang in there sounds like you only have a little further to go.
Regards,
Jay
