newhobby Posted December 21, 2009 Share Posted December 21, 2009 Hi all, I just retrofitted my BC29 hood with LEDs yesterday like many others here and have some questions. Let me explain my setup first, which is fairly similar to many others: - 12 Q5 coll white - 12 Q5 royal blue - 14" x 7.28" heatsink from heatsinkusa.com - 2 meanwell drivers ELN-60-48P - 4 rows by 6 colums with simple alternate pattern of whites and blues - no lenses - I adjusted the current to 1000mA with an ampere meter in series with LED. I have not tested the upper and lower extremes, but it seems I'm just about the middle point. So I could go up or down with the amperage. I wouldn't want to go up, but maybe down perhaps. Now to my questions: 1. Is there a way to get the cutoff PWM to lower than about 20%-25%?? I would love to have dawn and dusk effect, but the cutoff is really high!!! When it cuts off, it is still very bright. 2. I setup to 35% PWM to start aclimatizing the corals to LED lighting. It seems that 100% is way too bright. Does anyone here uses it at 1000mA and 100% pwm?? What settings do you use in your tank? 3. If I do decide not to ever go to 1000mA and 100%, would it be better to just use lower amperage but full PWM variation or use 1000mA and set it to let's say 80%... So, in other words, which is better: 800mA and 25% to 100% PWM or 1000mA and 25% to 80% PWM?? 4. The meanwell drivers burst at about 5s after power is cut off and flashes once per driver, so I'm getting one flash from white and one flash from blue. Is there a way to minimize or eliminate this issue? 5. Since the position of white and blues are different and the beams are so concentrated, I'm getting displacement on shadows, creating a ghost shadow just like those 3D movies when you watch it without glasses. What have others do to this effect? I guess I'm used to a more smooth shadow transition. 6. Would a lightly frosted like material placed in the acrylic shield impact dramatically the penetration of light in the water? My idea was to get some kind of transparency sheet and paint it with frost paint and place in the shield. That would solve my problem with the 2 distinct shadows by dispersing light before it reaches the water. By dispersing light, I'd be loosing PAR. Would this be a waste of money on LEDs and I should just get used to new shadows? Thanks in advance for your responses. RI Link to comment
This topic is now archived and is closed to further replies.