Oh, I don't know much about malawi cichlids to be honest. I prefer Tanganyikans 
Prime is generally just used as a dechlorinater, but also helps with ammonia and nitrite in emergencies.
Basically you could be in a mini-cycle, which should be handled like you would a fish cycle. So I would:
1) Get a liquid test kit to verify
2) Do water changes to keep ammonia/nitrite as close to 0 ppm as possible.
IF ammonia/nitrite are out of whack (ie more than 0 ppm). Ultimately you just need time to rebuild the bacteria colony. Hopefully there is enough left over that it will not take long...
But for all we know your tank could be perfectly fine and those strips are just extremely accurate.
Prime is generally just used as a dechlorinater, but also helps with ammonia and nitrite in emergencies.
Basically you could be in a mini-cycle, which should be handled like you would a fish cycle. So I would:
1) Get a liquid test kit to verify
2) Do water changes to keep ammonia/nitrite as close to 0 ppm as possible.
IF ammonia/nitrite are out of whack (ie more than 0 ppm). Ultimately you just need time to rebuild the bacteria colony. Hopefully there is enough left over that it will not take long...
But for all we know your tank could be perfectly fine and those strips are just extremely accurate.
