Opposite light cycle stabalize pH
 

As with many reefers I have tried different things. After 40 yrs of reefkeeping, I have thrown a truck load of gagets away and went from Jaubert DSB plenums to mud refugiums to shallow sand beds. Nothing has intrigued me more than the light cycle for macro in the refugium. I first went with a 24 hour light cycle using Caulerpa. The idea was to prevent Caulerpa from going sexual. Not sure why, but it worked ok. Then the opposite light cycle became the standard to help stabalize pH during lights out. The logic of steady state pH has eluded me. There is no oppossite light cycle on the reef. Why does there need to be one in our marine aquariums. On my sumpless tanks there is no opposite light cycle. The pH fluctuations that I have seen go from 8.1 to 7.8. I have observed no problems with these pH swings in my tanks. It has actually assisted in dissolving arogonite for bufferring and trace mineral addittion.

On my 75G tank, I have a 4" DSB Jauberty Plenum with a mud macro refugium. It has been on an oppossite light cycle for ten years. Last week, I changed lighting schedule for tank and refugium lights to run simultaneous for 14 hours.

We shall see if modertate pH fluctuations are good are bad for a mixed garden reef.

Does anyone know what the daily PH swing is on a reef? Tried some googling and could not find a graph or anything. I did see a PH swing measured in kelp forests but that is quite different .

Just because its talked about/recommended in this hobby/forums doesn't mean its right..
Lots of opinions float around..
Just because it may make sense doesn't mean its needed or has any impact either..

http://journals.plos.org/plosone/art...l.pone.0028983

Looking through that it looks like the swing on the reef was .5, .1, and .2 from their three measurement locations

http://journals.plos.org/plosone/art...e.0028983.g002

Edit: Sorry for the size...

I think what is easily forgotten is the sheer mass that the ocean is. The amount of change required to make a swing that would be easily done in our aquariums is insane.



Sent from my iPhone using Tapatalk

Jayball,
Thank you for the data. In looking at differrent locations in the oceans, it seems as if there are fairly large fluctuations in pH (.5 to .1).
I can not see the need for steady state pH in our marine tanks.

Perhapes someone with a micro biology background may have some input to this question.

I think most experienced reefers will tell you not to 'chase' pH. Seems to bother us more then the animals under our care.

Laissez Faire Reefkeeper
 

My first marine aquarium in 1971 was a Galveston Bay biotheme. We did not have hobby forums are the internet. I collected water on an incoming tide at the Galveston jetties. For substrate, I used crushed up oyster shells that were purchased at a chicken feed store. I chased pH for three months until the fun was gone. Once I left it alone, everything flourished. I do not like my hobby to make me work as I am a laissez faire reef keeper.