We use 100 L aquaria. One can raise 25 or more adults in a tank of this size. Try to avoid holding more than 100 juveniles in one aquarium. Spread them more thinly to minimize strain on the filters and to see them grow at a reasonable rate.
Use 1 or 2 kg coarse washed limestone. This keeps the water hard, which is best for minimizing disease.
Use plain dechlorinated water. Do not use water obtained from copper pipes, the copper ions will kill the fish. Add about 3 Tbsp of baking soda to bring pH to about 7 (Vancouver water is acidic).
Add salt to the water as it aids fish health. Add 100-200 g of Sifto "Ice Salt" to each 100 L aquarium. F2 hybrids made from crosses between freshwater and Little Campbell River marines (LCM) develop poorly at low salinity. Instead of the above procedure add 500 g of synthetic sea salt (Deep Ocean Synthetic Sea Salts, Premium Reef Formula), which brings salt concentration up to about 5 ppt.
One airstone per 100 L aquarium is fine. Keep the flow light when the fish have just hatched, because they are not strong swimmers.
17 degrees C is perfect. Above 20 is flirting with danger.
External power filters have proved the most successful method of filtering, preferable to box filters or undergravel filters. External power filters are most convenient because they circulate the most water and are more easily maintained. We use one or two Aquaclear 200’s per 100 L aquarium. The foam inserts last a long time but need periodic cleaning. Do not bother buying extra charcoal inserts when the first set wears out, they are extremely expensive. Instead, buy bulk activated charcoal and roll some up in doorscreen with elastics to fit the space in the filter. We also put a bit of angel hair in the filter box for extra surface area and filtration of fine particulates.
When raising young fish from eggs, we turn on the power filters after the baby fish are free-swimming plus a few days. Then we turn on one filter at a very low flow (attained by lifting the intake pipe until the flow slows to a trickle) and with a fine screen mesh bag over the intake end of the intake pipe to prevent sucking up fish (this gets plugged up and needs a rap once in a while, but its worth it). Gradually we turn up the flow over the next 3 weeks, and eventually the second filter as the fish age, and also remove the mesh bag from the intake end. Clean filter insert or replace charcoal insert (but not both) once every few weeks.