a smart online retailer will stick to the knitting.
Clownfish, Chromis, blue and yellow tangs etc......
The easy to move stuff...... expenses can be offset if there is a high packing fee... but it is a different model then the corrent importers, as you will prob make more per fish/coral then the wholesale wholsalers, you would not have to sell as many, could be small, dynamic, niche....