How soon can I add fish to new tank with mature filters?

  1. JaneGael Member Member

    I'm setting up two new tanks. Both will be getting filters that have long been in established tanks. The 20L will get an additional sponge filter from an established tank. Driftwood and plants from the existing tanks will also be added.

    I need to:

    #1. Transfer fish from a too-small tank to the new 5g. This one will get and older sponge filter.

    #2. Get my temperate river tank up and running. Petco has some long finned danios I'm coveting as they will fit the temperate range and should be hardy enough to deal with a semi-new tank.

    I don't know if I need to wait a few days, especially with the 5g, or can move them tomorrow or Monday.

    The last quick setup I did went well, but I really don't want to kill 3 more platties or a school of danios.
     
  2. JFreshwater Member Member

    What fish are going from a "too-small tank" to the 5g? A 5g is still very small and is limited with what types of fish you can keep.
     

  3. JaneGael Member Member

    The 5g is a quarantine tank for 3 platties. They will be going to a 30g in a couple of weeks. They are in a 2g at the moment and are doing well, in that they are eating like horses, begging every time I go near them and are alert and active.