What Length Of Lighting Tube ?

[kiriyama]

Hi , tank is 48" long, what would the normal/usual length of lighting tube used be ?
Any feedback advice much appreciated

 

[elisew]

I`m no expert but..... Arcadia do 42" and 48" tubes so I personally would have thought that if you sit your fittings 3" in from the outside edge of the hood a 42" would be ok?

 

[JoshuaA]

For T8 bulbs probably the 900mm tubes and for T5 possibly 850mm.

If you have one already installed then just look at the length stated on the tube.

 

[kiriyama]

900mm , so about 36" in old money Cheers had originally planned 42" in a 5' , now I know what I'm looking for , cheers again

 

[JoshuaA]

900mm , so about 36" in old money Cheers had originally planned 42" in a 5' , now I know what I'm looking for , cheers again

If its a tank you are constructing a lid for then it all depends on what light design you are using. I just upgraded from T8 to T5 and spent hours and hours looking into it and have learnt a lot.

Most tanks I came across the light unit if fitted in the hood was a few inches smaller than the length of the tank and then the bulb was even smaller obviously.

The measurements I gave you were purely based on what I discovered, that most bulbs which were a mere inches under the tank length weren't suitable. For a 5 footer I imagine if you could probably find a light unit to accommodate 42" bulbs.

 

[N0body Of The Goat]

You might have seen my post a while back about messing up with the purchase of an Arcadia dual control unit from Titchfield about two months back, where I thought the control unit could accept a range of T8 tubes of differing lengths/wattage (now learnt with at least T8s the wattage and size and directly linked), when in this unit I bought could only safely power up T8s of a certain size.

Well the store I bought this Arcadia control unit and two tubes from were great at resolving this for me... I collected an Arcadia IP67 as a replacement control unit, which can power tubes that are 18-40W (60-120cm) and do not have to be a "matched pair." The only downside was that the IP67 does not appear to have independent switched for each tube, but the circuitry is set up so that if one tube blows the other will still work.

The irony is that having now got a setup that fits the purpose of lighting the 5-footer in the garage, I have felt the need to insulate the tank with polystyrene between the lid and the condensation trays because of the freezing temps, so the fish are going to have to continue to make do with my 48W portable SAD lightbox until it gets warmer!

As for how long a tube you should fit in your 48", a big consideration will be how much light is appreciated by the fish going in this tank (although you could always use a layer of floating plants in a not so high current setup to dim things down a little), plus the light needs of any real plants (although I'm presuming this is for your Tang setup, so you may not have any greenery to speak of).