Dunno how accurate this is, I'm no expert but seems in line with other places I've read about stocking and tank sizeWhat's the ideal tank size for 2 or 3 Platties?
How Many Platies in a 5, 10, 20, 30, 40, 55 Gallon Tank? | Fish Parlor
It is recommended to keep a group of at least 3 to 6 platies together. Stock 3 platies in a 5-gallon tank, 6 in a 10-gallon tank, 12 in 20 gallons, 21 in 30 gallons, and 27 in 40 gallons. Maintain a ratio of 2 female platyfish to 1 male at all times to reduce stress on the females.
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