I have a 20 gallon fish tank and the ammonia is .25ppm the issue is that the tank has been setup for 2 weeks had only 2 Molly's and I got today 8 neons,2 Molly's,2 angle, and two bottom bottom feeders how do I keep the ammonia from spiking and killing fish, I already did a water change today after putting fish in because the ammonia was higher than .25ppm (the water change dropped it to .25ppm) the LFS said ammonia chips any advice