So I when i upgraded to a 90g from a 46g i got new lights. two 250 mg with 4 t5ho. I guess it's been a little too much for my corals, a lot of them are starting to bleach. My question is how do re-start the acclimating to the light? Do I keep all the lights off for a few days or just the mh off. Then start turning the mh on for a 30 minutes and then add 30 minutes every other day? Will this work? How do I get their color back?
Coral Light Acclimation
- Thread starter JW3571
- Start date
Palting
New member
I made a small wooden frame, 20"x8", and attached 4 layers of screen and placed it on top of the tankm for a green stylo that was bleaching. It is working, and I plan to remove a layer a week until I can take the screen off completely.
Applying the same principle for your case, you can probably just lay 4 layers across the top of the tank, and start taking a layer off each week when the coral start to recover. HTH!
Applying the same principle for your case, you can probably just lay 4 layers across the top of the tank, and start taking a layer off each week when the coral start to recover. HTH!
edsreef
Member
That's the way I've always done it.
greenbean36191
Premium Member
You're trying to acclimate the corals to increased intensity, which has nothing to do with the duration of the photoperiod. The damage that causes bleaching is due to excessive intensity, so reducing the photoperiod does nothing to prevent that damage. All it does is allow less damage to occur before the lights go out. To prevent the damage from occurring in the first place you have to reduce the intensity, either by blocking some of the light, as with Todd's method, or by increasing the distance from the light to the coral. Reducing the photoperiod is not equivalent.
Now that your corals are already bleached, the best way to help them recover is to give them less light, more flow, and more food.
Now that your corals are already bleached, the best way to help them recover is to give them less light, more flow, and more food.
I did some playing around with a light meter and some common screening materials when I replaced my MHs a couple of months ago, and I was surprise by the results. Black window screening blocks a whopping 40% of light, which is still quite a shock to the corals when that last layer comes off. White egg crate blocks 15-40%, depending on the light's angle of incidence. Deer/bird netting blocks only 5%. I suspended layers of deer netting over the tank so that I could make the adjustments in smaller increments. In the future, I'll take a light reading before removing the old bulbs and another after installing the new ones. Caculating the percentage of light increase from the new bulbs will tell me how many layers of netting I need to reduce the new bulbs' intensity to match the old ones, and then we're back to peeling layers ever few days as posted above.
Palting
New member
Interesting!
