Lighting question.

[Little Luey]

Are T5's any better than power compact?
Is the MH the best light system?
What is the difference between the MH bulbs that have two ends as opposed to the ones that screw on to the fixture?

Lighting is soo confusing at times

[Geoff]

T5's are PC in a thinner tube. you are able to pack more into a smaller area. now whether or not this is a more elecrically efficient way to make the light is another matter. besides LED's which are not practical now, MH's produce the most lumens per watt.

the main difference between a SE (single ended) bulb and a DE (double ended) bulb is the lack of a glass shield. on an SE bulb the glass shield is incorporated into the bulb. it is what gives the bulb its shape. this is why you can run these unprotected over the tank (within reason). this shield not only protects the lighting element from water, but protects everything else around it from UV radiation. DE produce a significant amount of UV radiation.

G~

[AquaticCo]

DE bulbs produce far more PAR than mogul bulbs, in most cases. DE'S are also brighter, IMO.

Doug

[Geoff]

Originally Posted by AquaticCo

DE bulbs produce far more PAR than mogul bulbs, in most cases. DE'S are also brighter, IMO.

Doug

is this with or without the glass shield provided with the fixture?

G~

[Little Luey]

Originally Posted by Geoff

the main difference between a SE (single ended) bulb and a DE (double ended) bulb is the lack of a glass shield. on an SE bulb the glass shield is incorporated into the bulb. it is what gives the bulb its shape. this is why you can run these unprotected over the tank (within reason). this shield not only protects the lighting element from water, but protects everything else around it from UV radiation. DE produce a significant amount of UV radiation.

G~

So based on this it is safer to run SE bulbs, right?
Are the UV rays bad for the fish?

[Geoff]

only if the DE bulb is run unprotected. all DE fixtures come with a glass shield. as long as that shield is always on there is not a risk of UV burn. if it were to be removed than yes you can put critters in danger with to much UV radiation.

G~