Keeping live rock?

[JMM]

I purchased a tank that was running and had live rock in it. I am keeping it in a brute container with a power head keeping the water moving. Ammonia is 0, nitrites are 0 and nitrates are off the chart, literally. Did a 5 gallon water change and plan another tomorrow. Question is do I need to feed the rock and will the high nitrates hurt anything? There are a couple little crabs in the container as well.
Thanks for any suggestions,
Jim

[AJ]

As long as you keep the water moving, and heated the rock will stay live for months.  Just make sure to top it off so salinity doesnt get too high.

Having nitrates is good, it means that the rock is fully cycled and there are plenty of de-nitrifying bacteria.  If you want to lower it a bit, you could add a small light above the brute can and grow some Chaeto.

[JMM]

Thanks for the advice I did a 4 gallon water change yesterday and the water  was green. I will try to get some cheato somewhere. I am keeping the water topped off and checking the salinity.  Appreciate the help, thanks!
Jim