[WorkinMan]

Doing water changes during the cycle will only slow the cycle. Unless there's fish in the tank, I wouldn't do any more water changes, other than the fresh water top off's, untill the cycle is finished. About the additives, if you havn't already you'll need to get test kits for calcium and alk. Testing is really the only way to determine if you have to add anything. Here's something I have seen spread around on here-If you're not testing for it, don't add it. Having too much of something can be a bad thing in a marine tank.