Marine Lighting

[jetbox]

Tank lighting for a fish/invert new tank setup??? tank will be Betta lifespace 680

choice is either a 150w metal halide lamp

or

4x T5 luminiaire 24 watt

as T5's are reported to be so good and high light output maybe these are now better??? also lower running costs. How does the light output compare between these two setups?

 

[SkiFletch]

Tank lighting for a fish/invert new tank setup??? tank will be Betta lifespace 680

choice is either a 150w metal halide lamp

or

4x T5 luminiaire 24 watt

as T5's are reported to be so good and high light output maybe these are now better??? also lower running costs. How does the light output compare between these two setups?

If the Luminaire has individual reflectors for each bulb it will be about equal with the halide as far as Photosynthetically Available Radiation (PAR) is concerned. If it has one reflector and 4 bulbs, the halide fixture will far out-perform it in terms of PAR.

In terms of electrical efficiency, if the halide is powered with an electronic ballast, it will be about equal to the Luminaire, but if the halide is magnetically powered, the Luminaire will win.

Keep in mind bulb replacement costs. You have to replace 4 T5s but only one MH when the time comes...

Lastly, Halides give a shimmer effect, while T5's do not.

The choice (and a difficult one) is up to you.

 

[Musho3210]

T5s can mix and match to get your perfect spectrum since there are so many bulb types which is another pro of theirs. T5 gives a pretty much even amount of light around the tank if it is the same depth (minus the shadows) but MH will have all its power concentrated at one spot so you will get a lot of light in the center with not as much towards the sides. This can either be good or bad for you.

 

[pengy666]

Take a look at this?


MH lighting

Might be interesting for you too musho, I know you like facts

 

[Musho3210]

i already know of that site.

 

[1entra]

Another thing you may wish to consider is the heat produced by both lamps. I believe the MH will produce more heat than the T5's so you may require a chiller or fan to be fitted in order to not overheat your tank. This may also well lead to higher evaporation of water which will require constant topping up with freshwater. So in the long run it may cost more having to buy fans etc and more water loss with MH than T5's!

 

[Musho3210]

watt for watt they have the same amount of heat, and its easier to fan cool an MH light than it is to fan cool a T5 light since T5 spreads its heat all throughout the bulb while the MH is all concentrated. One small fan blowing away concentrated heat is easier than a few big fans blowing away not so concentrated heat. Both types of lights should be properly ventilated.

T5s are purdy hot bulbs.....

 

[jetbox]

Thanks all for your replies. I didnt think it was an easy decision and still can not decide...

running costs appear to be similar... I maybe favour the t5 as you can mix and match tubes

I am looking at arcadia t5 luminaires, not sure if these have seperate reflectors??

 

[SkiFletch]

Thanks all for your replies. I didnt think it was an easy decision and still can not decide...running costs appear to be similar... I maybe favour the t5 as you can mix and match tubesI am looking at arcadia t5 luminaires, not sure if these have seperate reflectors??

Most arcadias I've ever seen do have individual reflectors. They're a pretty high-end fixture (and higher cost too)

Take a look at this?MH lightingMight be interesting for you too musho, I know you like facts

Sanjay = the man . Came to speak at our local club a few months ago. Really intelligent guy and very experienced reefkeeper.

 

[xxBarneyxx]

I am looking at arcadia t5 luminaires, not sure if these have seperate reflectors??

I have two Arcadia Luminaires and they are very, very good. On mine (4ft 4X52w tubes) there is 1 reflector for two tubes (as far as I can remeber, will double check when I get home and change this if I'm wrong). They look pretty cool as well which helps if you have an open topped tank (see one of mine on the pic in my sig).

 

[jetbox]

i am favouring the MH now but is 150w mh enough or should I get a unit with a t5 too to add a different light spectrum.... or is the mh enough???

also mh need to run without a cover glass in which case evaporation is going to be excessive, will i need auto topup to with the mh?

and a friend has sais that he had mildew growth on the ceiling to to the evaporation? anybody else suffer from this.. the other half will NOT be pleased if that happens

 

[xxBarneyxx]

Sorry to go off topic but what do you think to the betta lifespace tank? the lifespace 1500 is one of the ones on my "potential new tank" list. Looks very nice and well put together in the store but that of course doesnt mean it is any good in practice.

 

[Musho3210]

MH is fine, you can mix both MH and T5 but you can also go your separate ways. Spectrum is more for you and not much for the corals, most corals will do fine from 6.500k (yellow and ugly, high in PAR, stimulates shallow water like lagoons and tide pools etc, but in the ocean deep water is not yellow and not high in PAR so this strong lighting is not needed unless you want a super acropora garden) to 20,000k (very blue, low in PAR but simulates deep water lighting)

Some people keep there tanks in only actinics but that has very very little par and it would start hurting my eyes after a while.....