ok so my cycle on my 40g has been going well.....until this week. I had been adding ammonia to keep the BB alive and it was dropping ammonia well not completely cycled but definitely speeding up. But the last couple of days my ammonia is stuck on about .5ppm and wont go back to zero. Its been like that for three days now (.5 would usually be gone overnight), whats wrong here? what should i do?