A short while ago, I did a sump build using a 40 gallon long Aqueon which included a refugium in my build.
I understood (correct me if I'm wrong) that a slow flow rate was required in a refugium for it to be effective as faster flow rates reduce the amount of time for macro algae to absorb nitrates and phosphates.
But I am noticing a film developing on the surface of the water over the refugium. I've seen this before in tanks and just added a power head facing the surface to increase agitation. But I can't do that in a refugium; right?
Other than siphoning off the film or the occasional, manual agitation, is there anything else I can do?
I understood (correct me if I'm wrong) that a slow flow rate was required in a refugium for it to be effective as faster flow rates reduce the amount of time for macro algae to absorb nitrates and phosphates.
But I am noticing a film developing on the surface of the water over the refugium. I've seen this before in tanks and just added a power head facing the surface to increase agitation. But I can't do that in a refugium; right?
Other than siphoning off the film or the occasional, manual agitation, is there anything else I can do?