What kind of algae problems would the dry rock cause?

Even the best dry rock will not denitrify very well, if at all, in the first few months or longer. Therefore the NO3 will build unless you do substantial water changes.
Also, if the dry rock is previously used live rock, it's likely a time bomb for phosphates. PO4 will accumulate in the rock, and any life in the rock once removed from water will die off, causing a dry reserve of nutrients that once wet, will leech back into the tank.

Hi David,

If you want to get rid of the phosphate go to Red Coral and buy some Foz Down. Add it to your tank as per directions. It immediately gets rid of Phosphate. I make and use it so I know it works and is safe.

Unless you are trying to culture your anemone I would only feed it every 3rd day.

Cheers,
Tim

I wouldn't get rid of any phosphate until you know you have phosphate. Until then it's just throwing more muck in the soup. Test, determine the problem, then treat accordingly.

Bio balls are out sockfilters are new and rowaphos is in. Got to get water tested and see from there