refugium lighting - 24hr yes or no?

[emoutz]

I've heard conflicting reports. Got a new sump for my 90 gallon - stocked with LR rubble, cheato, some hitchhiker calpura, green hair algae, and xenia. I've heard you should light a fuge 24/7 (to prevent algae from going sexual and maximize nutrient export) - but others say to light it only when your main tank's lights are off. Looking for opinions

[74nautique]

24/7 for me.

[colettem]

I think the going sexual thing is only important for the caulerpa - chaeto doesn't have the same tendency to do it. 24/7 lighting is thought to reduce the chances of this happening but I have heard of it still occurring even when lit all the time. One of the arguments for a reverse photo period is that it helps to stabilise the pH imbalance between night and day as the algae will be photosynthesizing in the night and using up CO2 when naturally the pH would fall compared to day time. Not sure though how important this is in practical terms.

[YoungReefer06]

I currently use 24/7 on my fuge which has several species of algae in it. I use the 24/7 for continued nutrient export, but i am thinking about having them turn off during the peak 5 hours on the tanks daylight for two reasons. One is that it will stablize the pH more and second because many algae need a dark period for cell division.
Thats just my 2 cents.

[aquaman67]

I found my chaeto grows better on an 18 hour cycle.

[Travis L. Stevens]

I would venture to say that Caulerpa species should be housed under lights 24/7 to prevent going sexual. Chaetomorpha on the other hand needs a cool down period. 12/7 for it.

[emoutz]

So shoudl calpuera be included in our fuges? Or should it be disgarded in favor of cheato. I've got both now, but I could easily eliminate one or the other. Sounds like 100% cheato is the way to go...

[drunktank]

reverse photo time- Have the refg light off while main tank is running, and then when the main tank is out, refg goes on. Thats how i've done it and thats how i normally tell others 2

[YoungReefer06]

I plan on getting rid of my calpuera and only having cheato and red garcilia.

The lighting would be the following:

Tank=9:30am-11:00pm
Fuge=7:00pm-1:30am

[pvtschultz]

<a href=showthread.php?s=&postid=6785885#post6785885 target=_blank>Originally posted</a> by YoungReefer06
I currently use 24/7 on my fuge which has several species of algae in it. I use the 24/7 for continued nutrient export, but i am thinking about having them turn off during the peak 5 hours on the tanks daylight for two reasons. One is that it will stablize the pH more and second because many algae need a dark period for cell division.
Thats just my 2 cents.

Funny that you said that. I think that I remember hearing something like that years ago in my HS biology class or something along those lines. I am currently running 24/7, have been for about a year now, but if I can get a little more growth by giving a night period, that sounds excellent. I will warn people though. I did try to go from a 24 hour photoperiod to a reverse one time and the macro did not respond favorable at all. You'll need to do it more slowly. Then again, my grape caulerpa is probably in its fourth or fifth generation now and might not need the night...