LED ideas for 58L tank

[GlassWalker]

Been wanting to upgrade the lights in a 58L Askoll Pure L tank for a while. This is a small tank with a lid mounted 24W PL tube, encased in a watertight enclosure. I've had the tank nearly 2 years now and I'm sure tube would have degraded in that time too.

I took it apart a moment ago to see what options I have. Was really hot in there. Using an IR thermometer, the driver was ~55C and the tube mount was over 60C! Plugging it into a mains power meter, the assembly was taking about 22W at the wall.

Anyway, I'd like to replace it with LEDs. I could work it into the enclosure, or I could remove the unit and mount it directly to the inside of the lid. I don't want to modify/cut/remove the lid in any way other than at most providing new mounting points for whatever will go in there.

The available area inside the lid is about 53x16x6cm. If I were to recycle the existing enclosure, I'd have at most about 33x11cm to play with. Not sure on depth, as there's many obstructions inside. As it is lidded, the electrical power shouldn't be too much as the existing one makes the top of the lid warm/hot to the touch as it is.

As one possible option, I was thinking there is the Interpet 470mm x3 LED which is rated at 7.2W. It is short enough to fit, but I'm not sure if that is "enough". I have the 1150mm x3 in my other tank. By itself that felt a bit dim, but that is a taller tank, so I might get away with it here. My gut feel is a little more might be required.

Interpet also do other lighting bars, but as far as I can tell those are 1.8W each and it'll take a fair few of them which would make the cost add up.

Just thought I'd check in case there were other options I might have overlooked.

 

[ourmanflint]

You can get single Beamswork 9w LED strips which are approx 250mm x 40mm x 10mm. You should be able to squeeze in quite a few.

 

[Lindy]

Tmc aquabars are designed for this kind of thing and come with fittings to attach to a hood. Very slimline.

 

[Lindy]

I think the aquabars are 12watt and a dimmer can be had for £13. I have 2 over a 80x60x45cmhigh tank

 

[dw1305]

Hi all,

This is a small tank with a lid mounted 24W PL tube, encased in a watertight enclosure. I've had the tank nearly 2 years now and I'm sure tube would have degraded in that time too.

It will still be working at ~95% of the efficiency it did when in was new. PL tubes are just T5 tubes folded in half and they show little light lumen depreciation before they fail.

Using an IR thermometer, the driver was ~55C and the tube mount was over 60C! Plugging it into a mains power meter, the assembly was taking about 22W at the wall.

I would be worried about this with LED's, T5's are fine at higher temperatures, but LED life will be drastically shortened by higher temperatures. Personally, because retro fitting a LED isn't easy, I'd just buy a couple of new PL24W tubes, enough light, cheap to buy and as you've already found cheap to run.

cheers Darrel

 

[GlassWalker]

Thanks all. Have looked at all the comments although still not 100% decided yet.

Beamswork strips - I'm having a bit of search fail here. Have found one place with what might be the ones (tubes with LEDs in them) but no price. Lots of unbranded similar looking tubes on ebay.
TMC Aquabars - looks ok, if a bit expensive. Need to look closer if the controllers can drive more than one unit. While I don't need all the power, I do like a more spread out light and personally I'm not a fan of too much "shimmer" from fewer high power sources.
PL tubes - I'm sure I read somewhere the fluorescent tube decay was, from memory, more like 80% of original output after 8000 hours, or roughly two years of daytime lighting. I believe for critical applications people change them at least once a year, but I don't consider myself in that critical category with aquaria lighting. Also I don't consider them efficient at all. Too hot for my tastes and decent LEDs are simply superior. I've upgraded all other tanks apart from this one to LED and love how cool they now run. I left this one to last since it is the smallest so has least impact.
LEDs in heat - I'm aware they don't like it at all and will suffer reduced lifespan. However I don't expect any LED I put in there to get anywhere near as hot as the PL tube does. For starters, the PL tube and driver are both enclosed in the same plastic box. The best part of the 22W measured at the mains is inside that box. I'm looking at less than half that power with LEDs with an external driver, so even peak temperatures should be a lot lower. Plus I'm not going to put it in the box as most aquaria LED systems are waterproof anyway. They will have the entire lid area to spread their heat more evenly.

Given the above, I think I still like the idea of the Interpet triple bar system, but the TMC aquabar is still a consideration I need to look at more closely.

 

[dw1305]

Hi all,
I'm not anti LED, I think in 10 years time all aquarium lighting will be LED, they are certainly are the future.

PL tubes - I'm sure I read somewhere the fluorescent tube decay was, from memory, more like 80% of original output after 8000 hours, or roughly two years of daytime lighting. I believe for critical applications people change them at least once a year, but I don't consider myself in that critical category with aquaria lighting.

This isn't true for electronically ballasted triphosphate tubes, they show very little lumen depreciation until they fail. Have a look at this thread <http://www.ukaps.org/forum/threads/eheim-external-when-to-renew-media.24946/page-2#post-341045>.

Also I don't consider them efficient at all. Too hot for my tastes and decent LEDs are simply superior. I've upgraded all other tanks apart from this one to LED and love how cool they now run. I left this one to last since it is the smallest so has least imp

I'd be surprised if this is a huge amount of difference in electrical efficiency in use. Optimised medium power LED's potentially give you about 110 lumen/watt against about 90 lumen/watt for a PL2 tube. The problem is that you need to be able to cool the LEDs pretty efficiently to get the quoted lamp life and power savings.

cheers Darrel

 

[ourmanflint]

here are the ones I was talking about. You would need to remove gooseneck and clip, which slip off. Mine came as a single row of 9x 1w LED's

http://www.ebay.co.uk/itm/LED-Pro-L...Aquarium-Clip-on-Light-white-9W-/171297517774

 

[BigTom]

 

[BigTom]

PL tubes - I'm sure I read somewhere the fluorescent tube decay was, from memory, more like 80% of original output after 8000 hours, or roughly two years of daytime lighting.

Seems to be another fallacy (see data above). To balance that I have seen some longer term graphs which shows a large drop off in fluorescent tubes after 20-30,000 hours, but that's 4-5 years of 12 hours a day so not really something to worry about.

Source for the above - http://www.nlb.org/index.cfm?pk=download&id=10362&pid=10225

 

[GlassWalker]

Thanks for the info. It would seem fluorescent tubes don't decay as fast as I thought. At least, not the better ones. I'm not in a hurry to replace the light in this tank so at least I can rest knowing the existing one is probably ok for a while yet. The lumens/watt is closer than I thought it was.

Still, experience on my other tanks has shown I can get away with significantly less LED power than T8 or T5 tubes. For example, my 2nd marine tank started with 2x24W T5 with reflectors, but it never felt bright enough. I've replaced that with a 120W LED unit, run at 40%, which if linear would also be the same power as the T5s before, but it looks a lot brighter and better colours. Similarly in another freshwater tank, I had 2x20W T8s on electronic ballast. This was ok, but now I run a single 25W LED bar to give comparable subjective brightness. Plant growth is also as good as it has ever been. And my 3rd marine tank originally came with 120W of PL tubes on magnetic ballast! To be fair it was used when I got it, and I don't think they were ever changed, so they may not be at their peak efficiency. I replaced that with a 35W LED bar and once again that gave a reasonable level although comparing brightness here is more difficult as the spectrum was more different.

The only place I still run fluorescents at home is for reptile keeping, as UVA/UVB is only readily available in T8/T5/CFL and not LED, yet.

When lumens/watt of LEDs are illustrated, anyone know if they use the peak value or the peak power value? The biggest downside with LEDs is that when run at their maximum power they lose efficacy. I've built DIY LED units before (custom spectrum for marine usage) and rather than run LEDs at full power, I'd rather run twice as many at half power. However the time taken to build these is rather more than I have available, and higher power commercial units have come down in price a lot too with 120W units at sub-£100. Obviously this would be massive overkill for this little tank even if run dimmed! Lower power units don't seem as developed yet but I will have a closer look at that ebay one.