Is Gradual Light Acclimation ALWAYS Necessary?

[64Ivy]

I'm wondering how many of you subscribe to the practice of placing newly accquired 'sps' corals on the bottom of your tank and gradually move them upwards. I've been doing it for a while now but lately I've begun to ask myself why? For bleached corals I think it makes sense. For corals coming from a tank lit by 175 watters to a tank lit by 1000 watters I'd think it makes sense. But for the majority of my new stuff, it seems the lighting set-ups are usually within the ballpark between myself, online vendors, LFS's, and most reefers tanks. So even in the case of coast-to-coast mail order, the only real lighting difference is the coral has been in the dark for 12 hours. That's only a little more darkness than they'd get in the tank every night! Does anyone out there forgo this acclimation process and if so, have you had any 'light shock' problems because of it?

[Rick O]

I always do this but lately it's more so I can decide exactly where I want to place the coral in the rockwork. I do think it's a good practice and I never lose a captive raised coral using this method.

[DKKA]

If I know where the coral is coming from and have some idea of what kind of lights they were using, then I usually mount directly to the rocks. I will sometimes shorten my photoperiod, and/or raise my pendant, just for a day or two, while I observe the coral. (I'm home all day, every day, with the kids so I am able to keep a close watch on new additions.)

I've never had a coral outright bleach on me. I have had corals slowly start to fade over a period of days, or even weeks and then have to be moved to a lower spot in the tank.

I think true acclimation takes longer than most of us allow for, so leaving the coral on the sandbed (where it will likely be getting less current than if it were on the rocks) for days, or even weeks never made all that much sense to me either. I prefer to give it prime realestate right off the bat. Of course the risk of shocking a coral is real, it's just never been a problem for me, even under 250 watt DE's.

Dan

[tdwyatt]

pick your placement right off the bat if your plan is to have the coral grow and develop for permanent placement (as opposed to acquiring brood stock) and place a pvc rack above the coral to hold 30cmx30cm fiberglass screen squares between the light and the coral. you may use 4 squares stacked on top of each other to form a good bit of shadow, then remove a square every 2 days until the last one, which may be removed for part of the day if more shaging is needed. This is especially true for wild specimens that may have been in near total darkness during shipping, sorting, and rebagging. Captive raised frags usually are not an issue, it is the ones that have either been in LFS with poor lighting to start with or when moving from deeper tanks to shallow prop systems. The use of squares when introducing specimens from trusted (read this as pathogen and hitchiker=free systemns) sources allows for locallized areas of acclimitization witout reducing the lighting to all the inhabitants in the system. If you use a holding/quarantine tank with less intense lighting than your display/prop system, then this would be indicated when doing the final transfer as well.

HTH

[yardboy]

td, I've heard your idea before, and agree totally, even though I've never done it because it seems like such a pain. Is eight days enough? Maybe not so much of a pain after all. Just have to build something.
Oh yeah, Tom, I sent you a pm.