Welcome Diana! The above advice is sound, unfortunately, your last post has raised some concerns.
Sea horses really do need species specific tank. I had originally wanted a couple sea-horses as well but when I started researching them discovered they are very sensitive to water parameters and need little to no water flow at all in the tank. This is the exact opposite for 90% of other SW
creatures that need a decent amount of water movement in the tank (most recommend 10 times your tank volume in gallons per hour) Trust me, my wife was not pleased with this news. Her conditions were, "you can have a SW
tank if you put a sea-horse in it"
also, the trouble with your crabs and lobster may have been how you acclimated them to the tank (you can read up on Acclimation
in our Articles Section
) invertibrates are very sensitive to Nitrates. So if your tests are actually accurate, that may have been the cause.
Also, research your chocolate chip star, they are predatory. Research your sea urchins before you buy one as well. They can grow fast and some can damage other things in your tank. Some are great tank inhabitants. Choose wisely
Don't let my cautions discourage you! this hobby requires a fair amount of research and a whole LOT of patience! and a spell checker!![/edit]
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