[jolona]

I've read a thread on adding sand to an existing aquarium. I have a 30 gal FOWLR, with 2 percs, blue tang and a yellowtail damsel. I would like to know the advantages and some disadvantages of adding sand. No I didn't get these because of NEMO. I had this tank set up about 5 years ago as a FOWLR and just recently started it back up. I love the hobby and am new to the forum, so hopefully I can broaden my knowledge and experience. Thanks for the information

[Reefland]

Hi jolona, Welcome to Reefland!

Before going into a lot of detail, it will be important to know what you currently have for a substrate in your tank. The answers will be a bit different depending on what you currently have.

If you have nothing in your tank now, a bare-bottom, you could simply add dry sand into the aquarium in any ammount that does not cloud the tank horribly. With any method you use, there is going to be some clouding when you add a fine grade, also called sugar-size or oolitic sand. Trying to keep it off the rocks is going to be a challenge though so the best bet is to turn off the pumps, add a little bit of sand (you'll have to judge what a little bit is) and then turn the pumps back on.

If you have an existing fine sand bed, then you can add new sand to increase the depth of the bed at rates of 1/2" increments safely, without harming the existing fauna. Again, you'll have to judge if you can add up to 1/2" or if you need to add less at a time due to the cloudiness.

If you have any other substrate, such as crushed coral, I would recommend you seriously consider removing everything from the tank, removing the old substrate; being sure to rinse the tank with freshwater and wiping it dry very well, and then set your tank back up using the total amount of fine sand you desire, keeping in mind that it needs 3"+ to become a working live sand bed. Keeping your rock and fish in quarantine for this period will allow you time for the cloud to settle, please your rock back in and then the fish after a week or so.

Good Luck!