Compact Flourescent

[Dubby]

I am not clear about Compact Flourescent lamps. Can they be used instead of regular tubes?

Can I use the same ballast? i.e. put a CF instead of my regular tube. That would be good as I could probably get more light for the same wattage

Which models (available in UK) are suited for planted tanks?

 

[Dubby]

Is there nobody out there who knows about these things?

 

[EddieW]

I'll give it a go Dubby.

<deep breath>

Compact Flourescents also known as PC (Power Compact) Lighting are usually made using T5 tubes rather than the usual T8 (slim) or T12 (normal) tubes. The T number tells you the diameter in eighths of an inch - therefore T5 is 5/8", T8 is 8/8" (or 1") and T12 is 12/8" (or 1 1/4"). The slimmer the tube the more light it gives off apparently.

However to cram even more lighting into a smaller space T5s are normally 'folded' so that two (or four) tubes run side by side. This means that an 8" long T5 will actually contain about 16" of tube - pic below.

This results in much more watts of light in the same space - an 18" T8 tube would typically be about 15w whilst a 16" T5 would typically be 36w.

The ballast, starters, etc. for your existing tubes would not be any good for T5s for two reasons (1) the wattage will more than likely be too high and burn out the unit and (2) the fittings for a T5 are totally different as they only connect to one end of the tube.

As regards what is available there are many out there - a lot depends on your budget. I have just purchased an ASL overtank lumineire with 2 x 36w T5s for a fresh water tank as I like the one I have on my marine. This will be replacing the hood totally which I am happy with as the hood is a pain (keeps drawing splashs of water up the sides by capillary action). THe unit I have gone for is available on line here - I use this site a lot for on-line stuff, they have other units which may be appropriate for retro-fitting into your existing hood.

Have a search around through the various on-line vendors and see what options you have, bear in mind that T5 lighting is still quite expensive, but at least its not as bad as Metal Halides.....

HTH, Eddie

Ooops - can't post a pic in this forum, I have linked to it on their site which they might not like....

 

[Dubby]

Thanks Eddie.

Do you know if it is just the connectors that are different or is there something fundamentally different with the ballast.

I want to put additional tubes (normal flourescent) and will need to buy a new ballast to support it. Whereas if it is the same ballast then I could just change the connector (may cost me as much as the ballast ) and power 2 CF tubes in the bargain. What do you think?

I will definitely need to look around to see where I can get the stuff.

What kind of CF bulbs do you use? Are there specific models suited for plants & aquaria ......... I will probably need not more than 40W as it is for a small tank (< 20gal)

 

[EddieW]

I am not sure whether the ballasts are the same other than the power rating - they look similar but there might be other differences that are not obvious.

I am sorry to have to say that I would generally shy away from messing with the ballast, just too risky especially with all that water near by. I have just had a check on my tank here at work and it is rated at 15w running a 15w tube and is quite hot to the touch - could well be a fire hazard if it was being over driven.

I have a roughly 20 gall planted tank that is just about to get the PC treatment. Currently has 1 15w tube which is going to be replaced by 2 36w T5s I will be increasing the lighting gradually so it doesn;t shock them too much. First will run for a while using only one and for a shorter photoperiod, then gradually start bring the second one on stream for a hour or so and gradually increasing the time.

T5 tubes come in various types just as the normal tubes do - daylight, actinic, 50/50, plant, colour enhancing, etc. I have ordered the light fitting which includes all of the electircs, etc plus a daylight white and a freshwater plant tube - total cost just under £74 including delivery. They do a smaller unit so if your tank is 530mm or less in length you can do a twin 18w unit with the tubes for £63 inc delivery.

You may want to consider getting a cover plate for the tank if you switch to an overtank luminaire to cut down on the evaporation, but they are only a couple of quid.

HTH, Eddie

 

[Dubby]

Thanx Eddie. Wish you the best for your conversion. Dont have that kind of budget the wife would not approve