Are the seas really calmer at night?

[Chin_Lee]

Originally Posted by Canadian Man

It was mostly in my tri color acro that was in the highest flow area in my tank. I added the photo cell to drop my controlled tunze to 1300gph at night. About 2 days after adding it I noticed a decline in the coral.

I did not realize that the photo cell addition could have caused it till i looked back in my journal and did some reading.

Jonathan
maybe its just the change that caused the decline. IME, when there's a sudden change of something it usually caused a slight decline in my corals but after a few days, they adapt and continues to thrive. How long was the tri-color positioned at the highest flow area before the change? Did it completely bleach or did it come back after awhile?

[Delphinus]

Originally Posted by StirCrazy

yes they are and it is eerie. having been to many tropical coastal cities I can tell you the wave action calms down at night (unless it is storming) and the water becomes calm.

I wonder though. How much is that effect due to the fact that winds (unless it's stormy) tend to die down as soon as the sun sets? The waves gets churned up by winds, but convection currents etc. basically dwindle as soon as there's no sun heating up the earth's surface.

I have no idea what is happening to the currents under the surface, as I have never done any night dives. But tides and so on keep going obviously.

[Canadian Man]

Originally Posted by chin_lee

Jonathan
maybe its just the change that caused the decline. IME, when there's a sudden change of something it usually caused a slight decline in my corals but after a few days, they adapt and continues to thrive. How long was the tri-color positioned at the highest flow area before the change? Did it completely bleach or did it come back after awhile?

The tri color colony has been in the high current area for the past 13 months. The colony was about the size of a soft ball. I have heard that larger coral colony's don't like sudden change so I can only assume that it didn't like the decline in current and did not recover.

I broke the tips off as the base of the coral was receding over a 4 day period. The tips have been reglued onto another rock and the coral is still alive but white. I can just see some light green in the polyps again. So hopefully it is comming back as it was one of my most favourite acros I have.

[AJ_77]

Wow, that is sensitive. I guess my frag's not moving.

[Willito]

Just last week while I was waiting for my new upgrades of the Seio 1500 to arrive, I was down to about 1000g/hr of circulation from 2500g/hr. In the middle of the night I noticed the polyp extension on the Acros has been longer than any other time before. It normally extends considerably at night, but on these two days, it was double or triple it's length.This leads me to believe that low current does benefit the corals feeding habbits in some way....good I hope. I may have to do futher testing to see what the long term affects are. No signs of decline or bleaching on any of the corals previously in high flow areas.