I was going to write this as a page and place it on the right hand side with my other articles, but I figured that I will make a quick and painless blog about it. So why are my corals fading or bleaching? Well mine are not but you may ask yourself that question from time to time, especially if your new to marine reef aquariums. Here are a couple of reasons why your corals might be fading.
1. Your lighting might be to new and powerful or they might be old and need to be replaced. If you just bought new lighting then raise the lighting system a few inches above from where it normally was before you bought the new lights. If this is not a possible solution move the corals in your aquarium to a lower level. If you haven’t changed your lighting unit’s bulbs in some time then I would suggest you do so. Old light bulbs can loose there spectrum and intensity there by affecting your corals.
2. Your reef’s water parameters are off, Test your alkalinity and ph. Alkalinity and ph are usually the the problem water parameters in a saltwater aquarium, however you should discount nitrates and phosphate as well. Nitrates and phosphate will more than likely cause an algae bloom before bleaching corals, see keep a keen eye for sudden algae blooms.
3. Parasitic organisms. These could include zoa eating spiders (yes coral spiders, a video to come at a further time on this), snails, fish and a whole host of other creatures that like to eat coral. My suggestion is to observe the coral at night with a red light to see if you cant observe anything bothering your corals.
4. Not enough flow, most corals and especially stony corals need a high rate of flow. The reason a lot of flow is needed is so that the corals can feed and breath. Most people would suggest soft corals need a flow 15-20 times the tanks size, lps corals in the same range, sps corals up to 40 times the tanks size. So my soft coral 46gallon bowfront reef needs at the very minimum 690gph to a 920gph flow rate. I keep it at around 1k to keep my crocea clams happy.
