setting up 120gl saltwater tank

[pacheco]

I am trying to set up a 120gl saltwater tank would like to know what kind of base need for bottom of tank also do I need to use lr or can I use rock found on ground. tank will be fish only set up.

[fishfirst]

Substraight should be marine sand from your fish store... Live rock and rock found outside is a lot different... live rock has benefitial bacteria, algae, and is a natural Nitrate sink (takes Nitrate out of the water). Using rock from outside is a big risk, it can have ore in the rock and this will kill your fish. Get some base rock from your LFS, and then add some live rock to it to seed the base rock... also do a fishless cycle with your tank, use cocktail shrimp, drop them in, and check your parameters in your tank until your ammonia, nitrites, are zero and your nitrates are present... this indicates the end of the Nitrogen cycle, and your water can be deemed "safe" for your fish. (Also salinity should be 1.022-1.024 use a hydrometer to test this)

[electrikat]

Please don't use rock you find on the ground. It has all kinds of heavy metals and pesticides in it. Do you mean "base" as in a stand or as in what to put on the bottom of the tank bed? You don't have to buy all your lr of the expensive kind. You can buy the cheap base rock for the main structure and then get a few pieces of really good lr to cover and seed it with. If you meant "base" as in stand you will need something that will hold upwards of 1000 or more pounds. Please don't use a desk or a dresser. If you meant "base" as in substrate you can either go with sand or crushed coral and each has it's pros and cons. And everyone has an opinion about it. Plan all your equipment as though you were going to go with a full reef setup(lights, filtration etc) because you will save a lot of money and heartache in the long run. Everyone says they are only interested in fish only but most eventually want to add an anemone or a coral of some kind. HTH