FAQ - Why is My Live Rock Turning White?

Q. Can someone tell me why my live rock is turning white? I have both corals and live rock in may tank. It has two rear mount Whisper 3's, one pulling debris or whatever from underneath the underground filter, the other pulling debris and whatever from within the tank itself. I use a Coralife fluorescent lighting, and it's on 24/7. The temperature varies from about 72-78 degrees, depending upon the temperature outside of the house. As for feeding the live rock, I wasn't sure you had to do this, so I haven't been. If that's the problem, I'm sorry. I didn't know and nobody told me that I had to. I had live rock before about 6 years ago, and this didn't happen then. As for water changes, I've done I think 4-10 percent changes already and use instant ocean mixed with tap water. I made tests all over again, now the only things that are higher than normal are nitrates at between 40 and 80 ppm.

A. From the information provided, it sounds like this problem could be contributed by many things, but lack of iodine, calcium, and overexposure to light are the most likely causes.

Iodine & Calcium - The iodine is what gives corals and coralline algae their color, and the calcium their calcareous structure. If you have a protein skimmer, it will remove any added iodine in 24 hours, and most times other additives as well. For this reason it is important to use a time released iodine, or turn off the skimmer for a period of time to allow the inhabitants to absorb it. Many aquarists highly recommend Kent Marine Iodine products, especially if you need the time released type. To learn more about this topic, refer to our Aquarium Care Resources Index.

Using Tap Water - When you do water changes with tap water, do you use a dechlorinator? If you haven't, start. The chlorine in tap water is toxic to all of your aquarium inhabitants. Another reason why you should not use tap water is that it can be a source of actually adding more nitrates to your aquarium. Rather than trying to explain this here, along with the many other problems tap water can cause, refer to our Tap Water Purification Methods. <p>High Nitrates - In a reef tank, the optimal amount you want is an immeasurable one! In other words, zero is best. However, 0.25 ppm, but not more than 5 ppm is acceptable. An undergravel filter in a reef tank is not the preferred method for filtration. UGFs can be a real nitrate factory, in turn contributing to your high nitrate problem to start with. For more information about this topic, refer to our Nitrate Control.

Lighting - Live rock and corals needs to sleep too. You have to remember that even in the ocean these inhabitants only get about 12 hours of light in a day. They are also under water and usually only get a diffused amount of light. You need to mimic these natural conditions in you tank. Don't leave the lights on 24 hours a day! Try 12 hours on/12 hours off, as well as changing to 50/50 fluorescent bulbs. For more on this topic, refer to our Lighting Resources.

For more information about live rock, read our 6 part series About Live Rock, as well as refer to our Live Rock & Berlin System Resources.