Hi Kim
Welcome!
1. A small amount of sediment at the bottom of the tank shouldn't be an issue. The best way to to remove this is to get a thin piece of pipe (like aquarium air tube) and create a siphon then suck it out of the tank into a bucket.
2. Live baby brine shrimp is the best food for some species of jellyfish, yes. Most of the jellies that eat fine plankton in the wild do well from LBBS but other species eat everything from live fish to other jellies.
3. One of the easiest jellies to feed are moon jellies, they grow quickly when fed either LBBS or the powder food that we produce. There are lots of other species that are recently becoming available and are hardier than moons in a lot of ways but some of them are trickier to feed.
Flame jellies do well in aquariums but will need to be fed some LBBS because they don't do as well on a diet of 100% powder food.
Blue Blubber jellies are very hardy when it comes to water quality, temperature and even salinity swings but we haven't found a good food which sustains them past 4-6 months yet. We are currently experimenting with different types of zooplankton. LBBS seems to be one of the best for blubbers at this point but we still aren't getting the life expectancy we would like to see
Spotted Lagoon Jellies do well in aquariums but need high power lighting because they are photosynthetic.
You can find more information on other species of jellyfish here:
www.exoticaquaculture.com
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