I have a green monti and a sunset monti that are losing their color. Everything checks out. 7.8 alk, 420 cal, around 1350 mag. Just recently started happening. Nothing added in the past 4 months or so. Sbreeflights. Any idea? I did stop waste changes for about 1 to 2 months in order to figure out mag issues but that's it
Diagnosing coral color losses is a difficult thing to do without actually seeing the tank and having a lengthy conversation, but let’s start with the basics:
Are the colors fluorescent (glow under a blue lamp) or no? Non-fluorescent colors are generally induced by strong lighting, while any number of issues can affect the core (fluorophore) of a fluorescent protein.
Has anything changed in the tank? New lighting? Recently replaced lamps? If LEDs, have they been moved up, down, sideways? How often do you clean the protective clear lens? Do you monitor light levels (PAR)?
What sort of lighting? If metal halide or fluorescent lamps, how old are they?
How the water circulation pumps been cleaned lately? Were they put back in exactly the same spot? If you use a foam cover (such as EcoTech uses) has the filter been cleaned lately (a dirty filter can really reduce flow.)
Have you overdosed on kalkwasser (even once) before (or since) the color loss? Some proteins are sensitive to even a single pH swing.
Have you dosed the tank with an iron supplement lately? A bad thing (for coloration anyway) if heavily dosed. It’s a fallacy (in some, not all cases) that high nutrients will cause color loss.
Some things are really difficult to track down. For instance, a company contacted me a few years ago and said their office reef tank corals were producing a pink slime. To make a very long story really short, it turned out a chemical used in their manufacturing process (in another part of the building) was stressing the corals and causing this.
