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causes ammonia levels to spike, often resulting in fish death. Starting with 20% of the total fish capacity is a good rule of thumb. This allows the appropriate, system-specific biological organisms to colonize. If using a fish-less cycling strategy, household ammonia can be used. It is important to source surfactant-free ammonia, as it lacks detergents commonly added to these products that are unsuitable for the system.
Low dissolved oxygen (below 5 mg/L): increase aeration, reduce feeding until corrected
Low pH (below 6.0): add base (calcium hydroxide, calcium carbonate, potassium hydroxide or potassium carbonate), reduce feeding until corrected
High ammonia (above 1 mg/L TAN): reduce feeding until corrected, perform 20% water exchange, check for accumulated solids, increase biological filtration
High nitrite (above 0.5 mg/L): reduce feeding until corrected, perform 20% water exchange, increase biological filtration
Consistently high nitrate: reduce fish biomass or feeding rate, add more plant biomass
Nitrate consistently at zero: increase fish feed or fish biomass
Low alkalinity: add carbonate bases ex. (calcium carbonate, potassium carbonate)
*Note: Adding any base to the system must be done with care. Small additions of these chemicals result in a large increase in pH. Base additions should be calculated before addition. Always err on the side of caution.