Refill test tablets are available for all Dry-Tab tests. Overstocking, overfeeding, and bird waste can cause a harmful ammonia build-up. It is important to monitor ammonia concentrations when starting a new pond, or when fish feeding begins in the spring. The level of ammonia indicates the activity of the biological filter and generally helps to define the quality of pond water. It may be present with ammonia if there is overstocking or overfeeding.
Excess nitrite prevents blood from carrying oxygen, and leads to death.
The level of nitrite is an indicator of activity of the biological filter as well as of pond water quality.