Suddenly I got fed up with transferring peat from a box/bag into a small tank, adding water, putting all peat back in a bag/box afterward. I now hatch the fry straight in the box where their peat is stored in. One liter or 0.5 liter plastic take-away boxes are used for storage+hatching. I buy them in a Chinese supermarket, per 50 or 100. I add rainwater from a tank to the peat in the box. After one or two days, the fry (if there are any) are poured off into a different tank. Drying the peat for the next round: I close the lid again and put the tank on its side. All water usually drips out soon. I am contemplating to construct some sort of dam-net-rake which allows me to pour of all excess water quickly.