Hi All,

Here is a recent post from Dr. Ron on the Reef Central Board about the optimum lighting cycle for macro algae:
http://www.reefcentral.com/vbulletin...threadid=16041

I was rather surprised by his response because I was under the impression that he was not a fan of a 24/7 lighting cycle, i.e. that he supported the theory that macro algae needed a “rest period” for optimum sustained growth.

Personally, I do use a 24/7 lighting cycle on my algae filter/refugium and have experienced high growth rates of the macro algae. But I was primarily drawn to this approach because of the evidence that this method helps prevent the macro algae “sexual crash” syndrome.

However I have also had conversation with others that use algae filtration that definitely seem to get better results with a reverse daylight cycle.

Bottom line is that if you are interested in algae filtration, maybe you should try both methods and determine which on works best for you.

Regards,

Scott


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The definition of an expert is a washed-up drip under pressure.
You can see my reeftank at http://www.homestead.com/spasse/

Hi Scott
A little off the topic but I have a question. I was just looking at the pics on your site. Do not take this the wrong way but it seems like you have a lot of what appears to look like slime algae(or at least unwanted algae) on your LS and LR in your main tank. The reason I ask is when I was playing around with a refugium on my tank and started to notice the same thing. About a month after I removed it all the unwanted algae in my main tank disappeared. I have recently looked at other tanks using Refugiums and Algae filters and seem to notice the same thing. I personally like a very clean looking tank and the algae was making me crazy, that was the reason for removing any type of refugium from my system. I was recently thinking of using a EcoSystem on a 37gal I am setting up but have since changed my mind after seeing some posts from Aquarium Maintenance guys talking about having algae problems in display tanks using these systems. What are your thoughts on this? Have you noticed that algae in the display tank is difficult to eliminate with this system?


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We as hobbyists need to respect the reef, educate and learn so that it will live on for all to enjoy.
bajathree
Come Dive Into
Baja3Reef

Bajathree,

I do occasionally get small patches of cyno on the live sand. They usually don’t last very long. My baby queen conch chows down on that.

I also have some rock that has some red turf algae, probably this species:
http://www.globaldialog.com/~jrice/a...ge/redturf.htm

and other patches of turf algaes scattered about. But only the occasional tuft of hair algae.

Most of the discoloration on the sand that you see is due to red calcareous algae.

My cleanup crew is minimal as far as snails and hermits are concerned.

I guess my philosophy about algae is that as long as nuisance algaes don’t reach “problematic” levels I don’t mind their presence.

My current system also features primarily lagoon type LPS corals. If I were trying to keep a pristine SPS only tank, I would be perhaps, more concerned with trying to eliminate all algae from the main tank. Whether this would preclude the use of a refugium/algae filter is TBD. I believe that a combination of heavy feeding, a mega-skimmer, herbivores, and algae filtration could be worked out, that would give you that pristine look.

Regards,

Scott

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The definition of an expert is a washed-up drip under pressure.
You can see my reeftank at http://www.homestead.com/spasse/

Originally posted by SPASSE:

I was rather surprised by his response because I was under the impression that he was not a fan of a 24/7 lighting cycle, i.e. that he supported the theory that macro algae needed a “rest period” for optimum sustained growth.

I wouldn't read more into that reply than is there. It seems to me Doc Ron was not expecting the results he observed 5 years ago during his brief experiment with a sump/refugium on his tank. All of his tanks now are run with hang-on skimmers and no sumps. In fact, he is asking the poster to perform his own experiments with different lighting cycles, saying that he would be interested in hearing the results. Seems to me he is reporting what he observed but not claiming that the data is sufficient to be conclusive.

Scott, maybe you could perform your own experiment to determine if the macroalgae in your refugium shows any difference in growth rates related to the photoperiod. You have to admit that a 24/7 cycle cannot be considered "natural"... not on this planet.

Personally, I do use a 24/7 lighting cycle on my algae filter/refugium and have experienced high growth rates of the macro algae.

The high growth rates could be due to available nutrients and unrelated to the lighting cycle. It would be interesting to see if you measured significant differences in growth rates with 24/7 vs. 14/10 (14 hours lit, 10 hours dark). Like Dr. Ron, I would be interested in hearing the results of such an experiment.

But I was primarily drawn to this approach because of the evidence that this method helps prevent the macro algae “sexual crash” syndrome.

This result would be the more logical based on the assumption that the 24/7 lighting cycle is "unnatural" and interferes with normal reproduction.

However I have also had conversation with others that use algae filtration that definitely seem to get better results with a reverse daylight cycle.

This is the more logical expectation.

Bottom line is that if you are interested in algae filtration, maybe you should try both methods and determine which on works best for you.

This would be extremely interesting. I wonder if anyone else has experimented with different lighting cycles and noticed differences in growth rates and sexual reproduction activity.

The logical expectation would be that maximum growth and maximum sexual reproduction would result from a cycle that included a dark period of approximately 10 hours in every 24. A 24/7 lighting cycle could be expected to inhibit sexual reproduction, but if it also results in increased growth rates, that IMHO would be unexpected.

Has anyone else tried this already????

Thanks,

Ninong [img]/ubb/smile.gif[/img]

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Irrational Exuberance!

Originally posted by SPASSE:
Bajathree,

Most of the discoloration on the sand that you see is due to red calcareous algae.

Doesn't that start clumping the sand?

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We as hobbyists need to respect the reef, educate and learn so that it will live on for all to enjoy.
bajathree
Come Dive Into
Baja3Reef

I just got my refugium lit and filled with the macro's that were in my display. My plan was to light on reverse cycle initially, but was concerned about a sexual crash so I went with 24/7. The algaes have had excellent growth rates in my main display, which is obviously on a "natural" cycle. I will monitor the rates in the refugium over the next few weeks to see if there is a noticable difference in the growth. As Ninong mentions, this will not give absolute data since the amount of nutrients is an obvious contributor of the growth. I am just completing the cycle so there is plenty of nutrients available in my tank at this point.

As far as I can tell plants don't need a dark period to grow. In higher plants the lenght of the night is more important than lenght of day. In other words with mums and pointsettias lights turned on for a few hours a night will keep them in a vegatative growth. Some plants are more sensitive than others. This light doesn't have to be that intense, there are cases of car headlights inhibiting flowering, of course street lighting is the biggest head ache. So the real question would be is ambient room light enough to prevent sporulation so then you wouldn't have to run the bulbs 24 hours maybe only 16 -18 hours would be sufficent.

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"The octopus notices the little cowries."

Hi All,

I will be experimenting with a reverse daylight cycle after my house move. [img]/ubb/frown.gif[/img]

“Doesn't that start clumping the sand?”

Does not seem too.

The actions of my cleanup crew and sand fauna may be preventing this.

The only time I have ever had a sand bed clump was some years ago on one of my first plenum systems. IMO, this was caused by a combination of lack of sand bed fauna, low magnesium levels, (Coralife salt) and a CA reactor that was not being watched closely enough.

Regards,

Scott

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The definition of an expert is a washed-up drip under pressure.
You can see my reeftank at http://www.homestead.com/spasse/