T5/t8 Question

[tmreynolds]

This may be a silly question, so please don't laugh!

Does a 24w T8 give out the same amount of light as a 24W T5?

Thanks,

 

[SkiFletch]

No, it consumes the same amount of electrical energy, but both Lumen and PAR output is higher for a T5 over a T8 of equal wattage. General rule of thumb, T5HO > T12VHO > T5 > T8 > T12HO > T12NO at the same wattage. Also remember, a 24 watt T8 is longer than a 24watt T5

 

[tmreynolds]

Cheers mate, as always!

The reason I ask is this. I like the fitted hood I get with the Juwel aquarium, I get no evaporation, looks nice etc. But i don't like the T8's that are fitted in it.

But, you can buy an Arcadia i-Bar, which replaces the middle section of the Juwel hood but with HO T5's.

i-Bar

The only problem I have is that the T5 tubes would be 22" in the i-Bar as opposed to 30" with my current T8's, would they be too short for my 36" tank and not fully illuminate the whole tank?

So what would be best for my 36" wide tank 2 x 30" T8's (current) or 2 x 22" HO T5's (i-bar)?

 

[SkiFletch]

Well, what you're doing when you go from a longer T8 to a shorter T5 is essentially concentrating the light more towards the center of the tank. There will be more light in the center and less at the edges when you do this. Depending on the height of the lamps off the water you may even have "dark spots" on the edges and it can be noticeable. If it were my hood and I wanted more light, I'd gut it and squeeze a 4 x 39 watt 36" T5 lamp retrofit kit into it. But then again, I love DIY and you may not. Remember, when increasing lighting you WILL increase heat output. And by increasing heat output, you WILL struggle with tank temp in the summer, ESPECIALLY if the tank's room is NOT air conditioned. Fans are practically required on a closed-hood design with anything more than dual T8's to keep temps down in the summertime. Of course once fans are introduced, evaporation goes up thus your need for RO water goes up. In the summer, with my fans on I use about a gallon of RO for topup daily. In the winter with fans off (cause its COLD here) I only use 1/3rd of a gallon per day. Its a whole series of tradeoffs that you have to be willing to accept to increase your lighting significantly

 

[Squid]

There was a similar discussion in the planted forum a few days ago (just in case some of it is of interest)..

http/www.fishforums.net/index.php?showtopic=176916

Cheers
Squid

 

[tmreynolds]

I may buy one of these i-bars to see if its suitable to give mt HO T5 lighting.

My question here is, I currently have 2 T8's, one tube is the arcadia marine white 9500K and one tube is arcadia actinic.

If I get the i-bar the choices are an arcadia 14000k marine white and either another 14000k white or actinic blue tube.

Will the 14k T5 be more blue than my current 9500K T8?
If so will 2 x 14k T5's give a nice white/blue light or should I get 1 x 14k and 1 x T5 actinic? Or will that be too blue?

Thanks,

 

[SkiFletch]

Well each manufacturer's idea of white and blue is a little different, kind of like sometimes you need to go up or down a half shoe size depending on the maker . I'd go with dual 14000k

 

[tmreynolds]

Well each manufacturer's idea of white and blue is a little different, kind of like sometimes you need to go up or down a half shoe size depending on the maker . I'd go with dual 14000k

Good call, thats what I ordered a bit earlier

2 x High output 14k T5's + reflectors, plus a T8 actinic tube + reflector + starter which I will screw into the rear hatch on the hood. This way the actinic will come on an hour or so before the T5's and stay on after they go out for a while.

Cool.

I suppose with this lighting, I could be a bit more adventurous with corals?

 

[tmreynolds]

Well, what you're doing when you go from a longer T8 to a shorter T5 is essentially concentrating the light more towards the center of the tank. There will be more light in the center and less at the edges when you do this. Depending on the height of the lamps off the water you may even have "dark spots" on the edges and it can be noticeable. If it were my hood and I wanted more light, I'd gut it and squeeze a 4 x 39 watt 36" T5 lamp retrofit kit into it. But then again, I love DIY and you may not. Remember, when increasing lighting you WILL increase heat output. And by increasing heat output, you WILL struggle with tank temp in the summer, ESPECIALLY if the tank's room is NOT air conditioned. Fans are practically required on a closed-hood design with anything more than dual T8's to keep temps down in the summertime. Of course once fans are introduced, evaporation goes up thus your need for RO water goes up. In the summer, with my fans on I use about a gallon of RO for topup daily. In the winter with fans off (cause its COLD here) I only use 1/3rd of a gallon per day. Its a whole series of tradeoffs that you have to be willing to accept to increase your lighting significantly

Just found out the 2 lamps in the i-Bar are off set against each other so there is lumination at each end of the tank. Obviously it will be slighly brighter in the middle but thats cool. At least its not all the light in the middle 22" and none at the edges

 

[SkiFletch]

bonus

 

[tmreynolds]

I now have some decent lighting!!

The i-bar has now replaced my old T8's, so I now have 2 x high output T5's with reflectors in my hood.

I've also screwed another actinic tube into the hood too on a separate ballast, and I still have my LED moonlight.

So now the lighting phases can go moonlights, then actinic comes on, then after a couple of hours the main lights and the reverse in the evenings

Everything looks so much better under the new lights too! They really bring out the colours of the wrasse especially.