Calculate the correct medication dose for your aquarium's actual water volume. Accounts for substrate and décor displacement so you don't under- or overdose.
Gravel, rocks, wood, and equipment displace water, reducing actual water volume. A 100-liter tank with 20% décor holds only 80 liters of water. Dosing based on full tank volume means underdosing, which can fail to treat the disease.
Light décor (small plants, minimal gravel): 10–15%. Moderate décor (standard gravel bed + rocks): 15–25%. Heavy décor (thick substrate, large rocks, driftwood): 25–40%. When in doubt, measure by displacement — fill a bucket with décor and measure water needed to cover it.
Yes — medication labels recommend dosing per volume of water, not tank size. Using actual water volume is the correct approach. Overdosing (dosing by nominal tank size when real volume is much less) is a common cause of fish deaths during treatment.
Yes. Activated carbon absorbs most medications, rendering treatment ineffective. Remove carbon media before adding medication. You can add carbon back after treatment is complete to remove residual medication from the water.
Generally no — combining medications increases the risk of toxicity. Treat one condition at a time. If multiple diseases are present, choose the most critical one first. Always follow the manufacturer's instructions.