How much light?

I have a small refugium ( 6g ) and I'm using about 18w over it 8 hours a day. I put caulerpa in it but dosent look good. I also have 1 x 65w PC but I think it is to much. Please let me know what can I do to improve my refugium. thanks

 

a 65watt bulb is a good wattage for growing in that shallow of a tank what is more important is the color temp of the bulb 6500k is great for growing

 

18w has to be plenty, how is the water flow? if it is too fast you need to slow it down some
and where do you have your skimmer at? before or after the fuge area? try different kind of weed, if the skimmer is placed before the fuge that could be the problem

 

The flow it is slow and I have a separate pump only for the refugium that is in top of the sump. I forgot to said that the water in refugium pass by the UV and then to the refugium.

 

try speeding up the flow people have various opinions on the flow of water through refugiums i would say just play with it tell you plants look better. also you could try adding some iron to your tank.

 

there is your problem! you are killing the micro bacteria before it makes it to the fuge, you shouldn't need the uv but for special situations or in a quarantine tank, try putting it after the fuge else where

 

I'm going to start by moving my UV and adding some more flow. I just start to use iron a few weeks a go. Guys what about th ligths and time of them?

 

you mentioned you have the lights on during the day... i would set them to go on 8 hours at night, you want a reverse photo-period on your fuge.

 

I do have them when the display is off.

 

awsome, your on the right track, what types of macro's you have all in there, you might want to pick a few cleaner clams if you can, they are incredible at keeping the aquaiums water healthy(er);D