Hi there fishlorians! I have a question, what stocking rule do you go by for: Commons/Comets/Single-Tailed Varieties. Fancies/Double-Tailed Varieties. I go by the 20 gallons for the first fancy and 10 for each additional and for single-tails I go by 40 gallons per fish and say they prefer Ponds. *This is for Aquariums technically but since Single-Tails are Pond fish you can include those in.*

I don't know much about ponds, but for aquariums i say fancies need 20 for the first fish and an additional 10 for every fancy after. I don't know anything about ponds so I can't say anything about single tailed varieties.

Aquariums, 10g per inch for single tails, but every situation is unique. If one can tend to their fish daily, then this can change, if one does tank maintenance weekly, then I would go with the above rule.