In a 10-gallon tank, you can accommodate a slightly larger school of Celestial Pearl Danios. Approximately a group of 10-12 Celestial Pearl Danios can thrive in a 10-gallon tank. Depending on other tank mates in your tank, this number should be decreased to prevent increased bioload levels.
Their calming demeanor and compact size allow this. However, as always, don’t disregard the other species you might be housing alongside the Danios. Checking the tank’s bioload and ensuring every dweller has adequate space is prevalent to avoid undesirable stress and territory issues.