1. Where the small tank's PH stable at 6, temp. around 27c, its Ammonia level stay very high causing shrimps die... Anyway to lower Ammonia level without using chemical solution? (I have tried changing water (around 40%) for 2 days in a road, but the level still high).
p.s. all I have in the tank is a new filter, piece of wood with moss, and black sand - not sure what causes the problem???

2. The problem with my big tank is not as serious as the small, but still requires attention. ...Soon after I change the tank's landscape with new plants planted last weekend, the PH level changes rapidly between day and night time; ranging from 6.2 - 5.3. Anyway to make the PH Level more stable?
p.s. temperature @ 25.5c, GH= 60, KH = 20.
Thanks in advance!
