Difference between 420 vs 460 actinic bulbs?
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Topic: Difference between 420 vs 460 actinic bulbs?
Posted By: swiftra
Subject: Difference between 420 vs 460 actinic bulbs?
Date Posted: September 01 2010 at 1:24pm
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So maybe a newbie question but was just curious what the difference is between a 420nm bulb vs a 460nm bulb? Does one offer more growth for your corals? Thanks
------------- If you make it idiot proof, someone will find a better idiot! Well 100g crashed when I moved it. Starting a 50g cube now. |
Replies:
Posted By: Ryan Thompson
Date Posted: September 01 2010 at 2:56pm
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A 420nm bulb is a true actinic bulb and features light found predominately in the violet range.
A 460nm bulb is a blue bulb. It features light found in the blue wavelengths. 420 bulbs tend to have low PAR and provide little growth characteristics. 460 bulbs tend to have a lot of PAR and are great bulbs to use. Are we talking power compact, T5HO or T12 VHO? I ask because different brands of bulbs are better than others. |
Posted By: Lewy
Date Posted: September 01 2010 at 3:07pm
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So a 420 really isn't 'good' to have it just makes the tank look nice? If I put a PC with both 420 and 460 would I get good growth? ------------- 40 gal w/ 20 sump |
Posted By: Ryan Thompson
Date Posted: September 01 2010 at 3:09pm
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420 pops certain colors very well. 460 bulbs pop greens and oranges very nicely. Plus 460 bulbs have a lot of actinic in them as is.
IMO, for good growth you need a few things. First you need the full spectrum of lighting and second good water quality. I shift my tanks more towards the blue end of the spectrum and still see great growth! |
Posted By: SGH360
Date Posted: September 01 2010 at 3:10pm
| 420 is more for a freshwater aquarium as it uses more red spectrum than the blue that why it looks pinkish |
Posted By: Ryan Thompson
Date Posted: September 01 2010 at 3:11pm
Actually you won't find really any freshwater people using 420 bulbs. Actinic lighting does nothing for plants. There is next to zero red spectrum found in true 420 bulbs. |
SGH360 wrote:Posted By: SGH360
Date Posted: September 01 2010 at 3:12pm
| whoops my mistake thx for correcting me |
Posted By: Lewy
Date Posted: September 01 2010 at 3:16pm
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I like the idea of a fuller spectrum but where I have a small aquarium, its a 12 gallon eclipse I am limited on space. The hood I have can only hold one 13 watt PC and I found a site that sells what I hope is the correct bulb but they only offer a "White/White" and a "Blue/Blue". The maker of the hood offers a bulb but it only puts off 5500 K. The lights I orderd claim to put off in the white 10,000 K and the blue claims 420/460. I orderd both so I can try the out. Which should I use? ------------- 40 gal w/ 20 sump |
Posted By: swiftra
Date Posted: September 01 2010 at 3:58pm
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Thanks for the info. So have done some searching but so far been unable to turn up a chart or anything like that has all the different color temps and the main color they will put off. Anybody have anything like that or somewhere I can look? Hope this makes sense basically looking for something that says a 20,000K bulb will put off more ....... a 10,000k bulb will put off more ......... Hopefully that helps. Thanks
------------- If you make it idiot proof, someone will find a better idiot! Well 100g crashed when I moved it. Starting a 50g cube now. |
Posted By: swiftra
Date Posted: September 01 2010 at 4:00pm
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Also to answer the first question was asking for T-5's but I am also running MH's too.
------------- If you make it idiot proof, someone will find a better idiot! Well 100g crashed when I moved it. Starting a 50g cube now. |
Posted By: Mark Peterson
Date Posted: September 02 2010 at 8:49am
Begging your forgiveness, but a 13 W PC is not much light. It will not offer much in the way of growth and only a little in the way of illumination. If it were me, I'd modify it to take a larger PC tube or put the tank in the window to capture the enormous power of sunlight. Below is what the tube I was speaking of looks like in action. This was a Helios UltraGrow 36W PC. I would have liked it a little more blue but back then UV Lighting had not yet made its group of color popping PC tubes.  ------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member 
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Posted By: Mark Peterson
Date Posted: September 02 2010 at 9:04am
 The light spectrum changes as it descends through the water. The 400-500 nm (ultraviolet-blue) range of light reaches deeper than the light on the red end of the spectrum. The coral and algae we keep come from shallow to deep water. This makes things a little difficult when it comes to what light is needed for growth vs. what light shows off the colors. ------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member
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Posted By: Lewy
Date Posted: September 02 2010 at 4:48pm
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Mark, you don't need to beg for forgiveness. I totally agree I don't have much light. I actually have the small tank in my kitchen where it gets quite a bit of natural sun light. Thank you for the advice, I really appreciate it. ------------- 40 gal w/ 20 sump |
Posted By: Luckedout
Date Posted: September 02 2010 at 5:29pm
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The last couple of weeks the right side of my tank was getting hit with sunlight for about an hour each evening and I noticed a surprising amount of growth difference on that side. I know that sounds like a duh type situation but seeing it happen is something else.
------------- -Ben 90g Mixed reef www.body-balancechiropractic.com |