Refugium Lighting - 24/7 is Bad-Says Kent Marine University

[Anonymous]

Quote from there website:

One thing to remember is to never, never, never run the lamps 24 hours a day… NEVER! Just like plants, algae need a break from photosynthesis, and keeping the lights on all day and all night will cause the algae to enter a reproductive phase (i.e. they turn milky-white and disintegrate, releasing nutrients back into the system and lowering water quality). The best idea is to have the refugium lights (a pair of 6,500K tubes is usually ample) on 8-10 hours a day, or rather night (when the lights in the main aquarium are off). In a cycled system the hobbyist will notice rapid growth of the algae, indicating that they’re doing their job efficiently.

Here is a link to the entire article regarding the use of Marine Biosediment: http://www.kentmarine.com/kumb.html

 

[Anonymous]

hmmm, they cite the same logic that is used in support of 24/7 lighting, preventing the algae from going sexual. What gives here? :?:

 

[Anonymous]

I teach an introductory biology lab at my university. One of the experiments many students perform in my class is to have two of the same type of aquatic plant exposed to different light durations.

One plant receives 12on/12off light.
One plant receives 24on light.


In hornwort, cerataphyllia, salvinia, and azolla, the plants all seem to deteriorate and die and those that aren't completely extinguished have very reduced growth rates. The culprit is the 24 continuous light. The identical plant genet when placed in 12/12 light grows markedly well. Many of the discussions the students have revolves around references that state a photosystem breakdown if not allowed a recuperation time. Also, some of the more simple minded students quip that if all plants are made to live in Nature with 12on/12off light, why would changing it from what they are adapted to be expected to benefit the plants? Simple explanation, but so true.

I suggest for maximum refugium efficiency, running 14 hours light at night. This has the added ability of helping maintain alkilinity and carbonate system and preventing too much respiration at night, thus increases O2 levels or at least maintaining them. Although in a turbid reef tank, O2 is rarely a problem.

I cannot comment on the sexuality and problems of caulerpa spawning as I do not know much of the physiology of the algae.

 

[Roach]

12 hours on...12 hours off. It doesn't seem natural to have it on 24/7. 8O

 

[TopNotch]

Aside from the algaes pro/cons...Heres a general plus for the 12/12...

A normal tank will have a pH swing from morning to evening. In theory, if you have your refugium on the opposite time cycle, the pH swing will be negated or reduced.

 

[SPC]

Thanks for that explanation Brian, you are good for something . I also run mine 12 hours for the reason brian gave + to allow the critters to have a dark period.
Steve

 

[Anonymous]

Well, so far no overwhelming vote or argument for either approach. The poll shows a dead tie.

Hmmm!

With over 120 "views" I would have expected more "votes".

Come on guys, VOTE, even if you don't care to comment on your reason.

Thanks!

Louey

 

[danmhippo]

You big mouth Louey...... :?

Fine, I am running 24/7. But don't take my word for it because I am not a Biologist neither a chemist. I am just a bean counter. I cannot tell you what benefit there is for running 24/7, but so far, I am not seeing any disadvantage for doing so. I will continue running 24/7 until a marine algae specialist tells me to otherwise.

FWIW, The main tank is 12/12, but the caulerpa growth aren't doing any better then the sump running 24/7. Just my observation.

 

[Dwight Devore]

Louey,
I run 24/7 on my mangrove refugium , based on what i have been told .I saw this article at Kent Marine and was confused. I have posted this same question before with no response.( Thought maybe I had asked a stupid question) Don't we have any experts out there that can settle this debate?

:?: IKE

 

[Anonymous]

I went to 24/7 because when I was 12/12 the macros went sexual all the time. Since going 24/7 no plant sex.

RR :mrgreen:

 

[fishfarmer]

I was running a reverse cycle on my refug. 12 hours on at night. I recently switched it to 24/7 since I moved my system and tore up the refugium in the process. It's been about three weeks and the Caulerpa prolifera is doing great. I guess it's time to cut the lights back to a normal photoperiod :wink: . I pay the electric bill now so every watt counts.

 

[Minh Nguyen]

I run my refugium 12 on 12 off, mainly because there are many small animals are noctural. They are much more comfortable out at night. I try to provide a more natural enviroments for them so that they can 'do their things' and feed the tank.

 

[Jeff Hood]

I run a modified version of the 24/7. My refugium is a 150 gallon stock tank. I have the refugium divided with 100 pounds of live rock. Over the center of the live rock I have 3 65 watt LOA fixturs and on each end I have a 175 watt 5000K MH fixture. I run 12 hour cycles on the metal halides but in oppisite phase of each other and I run the PCs with one of them which is the side where my soft corals are growing.
The algae on the oppisite side of the light is under dim lighting but never complete darkness. The algae is growing like weeds along with other types of macro like Sargasum etc... The corals also seem fine and appear to be growing well.

Maybe dim is dark enough and still prevents the sexual changes we see in the calurpa sp.

Jeff

 

[suckair]

I have ran both 24/7 and 12 on 12 off.

I did not notice much of a change from either.
I do run a bug 10g tank and the lights have never been off for over a year. The light failed a few months ago and the grape macro all went sexual and crashed the tank.

FWIW

 

[Anonymous]

I've often heard that if you preen back the algae and prevent it from reaching its maximum space in the tank, then you will not have any problems with it going "sexual". Don't know how well that works.

 

[danmhippo]

If light level are not affecting the caulerpa as apparent, could the factor of caulerpa going into sexual being other factors? Perhaps CO2 level/ph? Or CO2 concentration in relationship to light?

------high CO2 + light = good growth
------high CO2/low ph + no light = stress?

 

[Minh Nguyen]

If light level are not affecting the caulerpa as apparent, could the factor of caulerpa going into sexual being other factors? Perhaps CO2 level/ph? Or CO2 concentration in relationship to light?

------high CO2 + light = good growth
------high CO2/low ph + no light = stress?

My Caulerpa goes sexual with stress like water change, prolong air exposure, ect. It also goes sexual when it is large enough. I just keep harvest itbefore it does. After 2 years, I just about to predict most of the time when it would goes sexual.
Anyway, when it does, my tank just get clowdy for a few hours and the corals and clams got fed. I try to remove them so I can remove nutrient from the whole system. My tank was ever harm from the Caulerpa goes asexual.

 

[SPC]

Posted by Dwight:
Don't we have any experts out there that can settle this debate?

-The experiment that Dr Reef posted about seems to be in the "expert" category to me, am I missing something?? :?
Steve

 

[SteveP]

Well this thread got me thinking so I'm switching to a 12/12 schedule to see what happens. My caulerpa haven't gone sexual yet, but I prune them regularly. If there's no change, I'm leaving it at 12/12. Like fishfarmer says, every watt counts, and with two tanks running in my basement, I need to save 'em wherever I can! :wink:

Steve
8{I

 

[mgk65]

I am, and continue to be, in the 24/7 camp.

My refuge hasn't gone sexual in over a year. I prune haphazardly. Usually when the refuge is full. :lol:

One thing we need to remember is that caulerpa is NOT a plant. It is a multicellular, large celled algae. It derives its nutrition from exterior contact in the water and photosynthesis. There is no vascularization and there are no roots. What we perceive as roots are really holdfasts.

I think that Kent Marine is wrong.

Caulerpa is ok, but for another species, look at chaetomorpha as an algae that does not go sexual. It grows like crazy for me too.

Another aspect of caulerpa is the possibilty of chemical toxins being produced. For this reason, I am pruning back my caulerpa and am looking for other macroalgaes to use.

mgk