Setting a tank up with Amphipods

[Cohenjl13]

In all my planted tanks since i do fish and not shrimpers, i always let the tank cycle with amphipods, once the tank is ready for fish ~month later there is lots of these guys hiding around in the substrate and filter to give a snack every once in a while.

Is this something that could be done with a saltwater tank as well, and since i have only a 9g tank im planning on having 1 small goby, do you think they would sustain him with me feeding less often, maybe once a day instead of twice.

Link for reference to the little dudes

https://www.liveaquaria.com/product/3054/algagen-amphipods?pcatid=3054&c=3468+2190+3054

Edit: Second dumb question. Does "Live Rock" only refer to rocks with BB already established on it, or is it the rock wet/dry that just supports the saltwater system?

 

[Sniperhank]

Live rock is mature rock with an established bacteria base, correct. Though if you buy live rock online you'll get stuff drug right out of the ocean and kept wet through shipping and will have who knows what in it.
And you can get a tank to produce pods to keep fish fed. There are some fish in the hobby that will only eat pods. Will the goby have that much interest in them being the other story.