i have a tank at the moment with just the usual community mix
will transfer some of the rocks out of that tank plus the filter into the new tank
then do the usual tests until i get zeros with just some food thrown in to generate the ammonia
it will be a mixed gender umbuna with some of the more docile
yellow tailed acie
and 1 more to decide
Be sure to buy clear ammonia without any surfactants.
I don't know what baby sterilizing solution is made of but many people use plain unscented regular bleach mixed with water to clean preowned aquarium equipment. Another option is to use household white vinegar if you don't like to use bleach.