HOB refugium - is light bleed a concern?

[California Crow]

I'm in the process of setting up a CAD39G tank, and I'm adding an AquaFuge 2 HOB refugium, as I don't think the space available in the stock sump is big enough. Now that I'm putting all the hardware together, though, I see that there's going to be a fair amount of light bleed from the fuge lamp into the main tank. I'd planned on a 12hr on - 12hr off fuge light cycle, opposite of the main tank lighting.

How much difference does it make if the main tank is never completely dark? Has anyone out there in a similar situation rigged some sort of light baffle? If so, what worked for you?

CC

[FranktheTankTx]

Yep... I have the same refugium on my 54g. I ended up running my refugium lights during the day along with my MH light. My pH is pretty stable and does not seem to fluctuate all that much at night with no lights on.

However, I did not notice any negative effects with the bledd off light at night when I originally ran it opposite main tank lighting. It just wasn't very dark in the tank - almost washing out my moonlight. I preferred to have a darker night w/ just the moonlight on - thus why I decided to run the refugium light during the day along with my MH.

Now with this said - I know how to fix this. You can do one of two things -

1) Fix up some sort of canopy for the CPR light fixture. This would cover the light and stop almost all bleed off.

2) Do not use the CPR light fixture and stands - but rather buy a Current Satellite PC fixture. They are wider than the refugium and will sit directly ontop of the refugium with out any stands or legs. Only thing I have noticed is - I believe thru photos the medium and large versions have an acrylic piece glued inside the refugium which seems to stop bowing. However, the small (what I have) does not have this piece & with out the acrylic stands I notice some bowing of the refugium.

I assume that this has no negative effects or CPR would have changed it by now. I have just decided to run the refugium lights during the day & it has no effect whatsoever on my tank's pH at night - problem solved.

I hope this helps - took a while to type.

[California Crow]

Yep, it helps very much. Thanks for the response. I'll definitely check into that PC ficture.

I've been jotting down various light cycle plans, also. If I can come up with something that gives me at least four hours with just the moonlight on, I think I'd be happy.

CC