Care and breeding guides for small freshwater fish, by a hobbyist who has bred a few of them. Every species covered so far is in this tank, at its adult length, in the water it uses. Pick one.
Drawn to scale: 30 cm from the waterline to the tank floor, every fish at adult length. Sizes, layers and smallest tanks come from each species’ guide. Numbered parts are in the parts list.
Every species, smallest first
The same fish as a list. Each row’s numbers come from that species’ own care guide, and each fish is drawn against the same centimetre ruler. Tap a fish to find it in the tank.
Species covered on NanoFishNest, sorted by adult length
Tank sizes are each guide’s smallest recommendation for a proper group. Lengths are typical adults; some guides give standard length, without the tail.
Breeding, in the order it happens
The guides here keep finding the same thing: getting a spawn is the easy part. Raising the fry is the hard part, so most of the work sits in steps four and five.
1
Sex and condition
Tell males from females, then condition the adults on rich food, often for about two weeks.
Many adults eat the eggs they find; dense cover, mops or a mesh keep some out of reach. A celestial pearl danio egg is about 1–1.3 mm across, a pygmy cory egg about 1.75 mm.