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, there are no dwarf species that will always by nature swim about openly in the aquarium. Most are very reclusive and only come out in reduced or no light. There is the Dendrochirus brachypterus
aka shortfin dwarf noted on <<wetwebmedia.com
>> as being "owner friendly" although rarer to the trade, may be an option. Through personal experience, I have also found the Dendrochirus zebra
to be an open swimmer.