I am curious if one can store live sand sealed back up as best you can for future use. Also I am curious if adding live sand to an already cycled tank will cause problems. About four months ago I wanted to add a little bit of sand to make up for substrate that I had vac'd out of the tank. I added some carib sea live sand. Expectedly my water was cloudy for a few days however it was for a couple of weeks that I had white film algae on my glass. I am at the point where I'd like to once again add a little bit of new sand (I like to keep about a 1/4" of substrate in my tank evenly) Is adding from the bag of once used live sand the wrong move? Is adding from a new bag of live sand going to throw off my already cycled and stable tank? Is there a suitable substrate I can use to top off the current sand without having an ill effect of the currently stable chemistry of my system? Thank you!