Lighting FAQ

[AMAZONIAN]

Hi all

Alanmin can you clarify for me please; are you referring to electronically ballasted flourescent fittings which are dimmable or using the term electronic as a generalisation for Flourescents over a tank?

Errol

BSc (Physics). AMIEE.

Specialist Lighting Engineer to World of Wearable Art

& Collectable Car Museum.

I2887

[alanmin4304]

I was told by a person at an electrical wholesaler and they used the term electronic for the whole fitting as opposed to the old t8s I guess. I

[Simian]

Hi all

Alanmin can you clarify for me please; are you referring to electronically ballasted flourescent fittings which are dimmable or using the term electronic as a generalisation for Flourescents over a tank?

Errol

BSc (Physics). AMIEE.

Specialist Lighting Engineer to World of Wearable Art

& Collectable Car Museum.

I2887

The old school wire would ballasts and plug in starters for fluros are almost extinct now(or should be), they were originally replaced with wire wound ballasts with internal electronic starters which were marginally better, ie flicker free starting and slightly more efficient, the new generation fluros T5 & T8 have electronic ballasts that provide the ignition pulse with pre warming of the electrodes prolonging lamp life and have replaced the current limiting function of the wire would ballast with electronics to do the same, eliminating about 10w (on average) losses per fitting.

As for electronics over water, Amazonian would I'm sure agree if any cct (circuit) board is not conformally coated (shiny varnish stuff over the tracks and components)and is operated in a damp environment, corrosion of joints will most likely occur causing failure of the fitting. The same thing would happen in Roto-vegas or Kawerau but much faster due to the high levels of H2S in the air.

[matthewY]

Keen to know abit more on the actual temperture of a bulb (not colour but how hot it can get). I've had an old t8 setup with 1 30W tube in it. Touching the case after 1/2 a day of it being on, it was very warm (you could leave hand on it with no problems but can feel how hot it was). I have since grabed a cheap atman PL from trademe, 2x 36W. Even using just 1 bulb for 2 or so hours, the case itself is boiling hot, much hotter then what the 30W case...

so, afew questions around this,

1: is this normal to be so hot (hard to describe how hot hot really is but pretty hot that you could but prob wouldnt want to leave your hand on it for more then 5 / 10 secs and after taking hand off, u can still feal a burn for the next min or so)

2: is it better to be hot? is this a sign that the heat from the lamp is actually being dispursed correctly (I'm thinking like a heat sink or something, where if the ehat wasnt hot, its not conducting heat well and therefore not good)\

3: fire hazard risk? the bulbs are used in plasic hoods so cant be too bad right? My hood is wodden (or mdf possibly???? propper manufacture stuff with a layer of black) and has a 10cm gap seperating teh hood roof from tank roof. I have the light unit pretty much directly directly on the glass with about 1/2 cm gap below (scared it woudl crack glass otherwise).

4: if the tubes are all the same in different units then the tube should produce the same heat? therefore could the heat be from the coals/ starter stuff and indicate a need for replacing them?

5: diffeerent type of bulbs (t5 vs t8 vs pl etc) cause different heat levels at same wattage?

[Ira]

I wouldn't worry about fire risk from a hot case. If you can put your hand on it for a second or two it's probably around 60° or so. Paper doesn't burn until over 200°, wood is in the region of 280°c or more. If the case is hot enough to start a fire your hand would probably stick to it.

The majority of the heat in the case is likely from the ballasts, but there will be a huge difference in temperatures due to airflow and ballast efficiency.

[matthewY]

wow, thats a quick response. really good to know it wouldnt be a fire hazzard.

When you suggest ballast, would replacing this with a more suitable one be a better option (and easy option) or is it a case of what u get is what u geta nd ur stuck with it?

thanks

[Ira]

wow, thats a quick response. really good to know it wouldnt be a fire hazzard.

When you suggest ballast, would replacing this with a more suitable one be a better option (and easy option) or is it a case of what u get is what u geta nd ur stuck with it?

thanks

More suitable than what? Than a ballast that's doing what it's intended for and is working properly? Maybe you could pull it apart, replace the ballasts with more expensive higher quality ballasts, cut some ventilation holes, put in a couple fans for circulation...And then you'll end up with cheap working light that you've made likely less reliable, uglier and more expensive.

The cases get hot, that's how they dissipate heat it's working as intended.

[maoripho3nix]

T5 and T5HO fittings have a higher watt per inch ratio as well. More power, brighter light.

Another thing that is more of a 'plant' topic than lighting, is most aquarium plants (green ones) need red and blue light. This is why we often recommend daylight 6500 kelvin or thereabouts, because it produces fair amounts of both red and blue. Warm white (2900 kelvins approximately) doesn't provide enough of the blue. I could give specific wavelengths for the various types of chlorophyll but that's beyond the scope of this topic.

I dont think its beyond the scope of this topic, after all lighting is required mainly by plants and coral.

Could you perhaps write something about the wavelengths and how they affect plants? Why the red and the blue ends of spectra are required for plants?

[phoenix44]

Why the red and the blue ends of spectra are required for plants?

Ill let someone else go into why you need certain types of blues and reds, but basically google the term "phytochrome" and do lots of reading. also plants need most of the light they get except the colour of the plant itself. that's why we see the plant as being that colour.

[phoenix44]

actually, im not done yet... :lol:

there... that's why they need those spectra

http://www.cbu.edu/~seisen/ChlorophyllAbsorption.jpg

http://www.ktf-split.hr/glossary/image/chlorophyll.gif

[alanmin4304]

You can see that the peaks are quite specific and do not exactly relate to the types of tubes generally available (not quite cool white or daylight).

There are countries where plants have been grown a lot under artificial light and some of these have developed lights producing the best frequencies. One problem is that these lights are generally developed for emersed growth and red light does not penetratrate water as well as blue. These lights are normally used to encourage plants to flower or fruit so they are not entirely what we might be after. So it is not just about blue and red light. I can say without a shadow of doubt that the best lights for you are the ones that work for you and the only way to sort that out is to experiment (don't forget to report back with pics)

[simfish]

Hi my question is:

I live in Manukau, Auckland. I would prefer not buying and paying premium for a branded T5HO tube. Is there any company that specialise in lighting where I could buy T5HO tubes and therefore not pay premium prices?

There was a company in Elleslie but I forgot where

Thanks

[Sunbird73]

bump.

Would also like to know where to buy reasonably priced T5HO tubes

[alanmin4304]

I get a good deal from lamp specialists down here but I don't know if they have that tube. They might get it in for you if they don't stock them.

[Sunbird73]

awesome, thanks. There is a one just down the road from me, convenient!

[GZ_Loach]

Can anyone tell me about the Aquastarlight Metal Halide fittings? Are they any good?

I'm looking at getting one for my 200L x 60H x 90D tank

[camtang]

Good Question Whetu, and quite a contentious one amongst some people here, I will answer the showing off the fish question now and get back to you on the plant growing one.

To show off your freshwater fish ie Africans to the best effect use a mixture of High colour rendering (Ra) tubes colour 940 and a high output or Efficacy (Lumens per watt lm/W) tube colour 840 (will make the tank appear warm and inviting) or colour 865 (will bring out the whites on the fish and give a sharp contrast some people find this light quite harsh tho).

Because Ra and Efficacy tend to be mutually exclusive you will need different tubes for each effect.

Bear in mind I am not talking about specialist aquarium tubes here, there are a myriad of different special tubes for various applications if you have a massive budget use those ones.

Salt water tanks tend to have very high colour temperature (sometimes 20,000+) as this tends to correspond with an increase in UV light which corals require to grow (metal Halides are good for this but I am sticking to fluros at this point)

I have looked at this a couple of times and I am still confussed. If I am changing my bulbs for just fish ( africans) What type of tube numbers should I look for to make the fish "pop"

[Li@m]

@camtag-Blue

[disgustipated]

great thread. cheers for bumping it cam.

as i understand now, generally, the higher the number, the better it is for growing plants.

[Li@m]

great thread. cheers for bumping it cam.

as i understand now, generally, the higher the number, the better it is for growing plants.

No not quite disgustipated. the best is about 7000k although Amano uses 10,000k i think.

[Godly3vil]

Im using 10,000k mh bulbs and they seem to do the trick.