You got lucky in the fact it was a gradual degradation of their habitat, after your previous attempt it would be good to get all test kits and get an understanding of water chemistry
Add plants, a couple of fish and a bit of driftwood and wait for a week then check ph before adding anything else. Things will change as the tank cycles.
lol, thought you would have answered.
still a cushion star, get some variation from 4 to 7 legs
what colour is the top side?
how long has the weed been in there?
Clean natural salt water can be collected locally in many parts of New Zealand; you just need to ensure it is clean. Collecting about half an hour before high tide is best but not after any recent rain as this can include contaminants from land runoff. Near river mouths or areas where there is a lot of boat activity should be avoided as well for the same reasons. Collected water can be stored indefinitely in sealed containers away from any light sources.
If you are worried about parasites ( I've never had an issue) put water through a 1 micron filter as all parasites are bigger than2 microns
The task of collecting water can be made easier by using a 12V pump that plugs into the vehicles cigarette lighter and then pumping into large sealable, food grade plastic containers.
Collection points around NZ., used by other local reefers.
https://www.zeemaps.com/map?group=2833137