What tube to buy

[Kriber]

Hi all, This morning I noticed one of my fluro tubes was flickering, it's sort of constantly lit at the ends though. This is a sure sign that its needs replacing right? Swapped the tubes around and this bulb still flickered while other worked fine in the 'old flickering slot'.

Anyway its a 3ft Aqua One lighting unit and the bulb was one of those pink ones that are meant to enhance fish colour (the other was a plant growth tube). Do the different types really make a lot of difference, the plant growth ones sure do seem a light brighter. What bulb should i go for? Also what were the makes/numbers of the suitable bulbs that are available from hardware stores etc.

I'm in Chch, well close enough really

Your help and/or opinions are most welcome

BTW I just noticed it seemed to shut itself off if only one bulb was in the unit, put the 'worn' one back in and the good one is working again (the tubes can be operated independant of one another as well). Is this normal?

[count_sexy_tart]

did you put a new starter in with the new bulb????

[Kriber]

Haven't got a new bulb yet! I thought the starter would be somewhere else in the unit. Surely the starter doesn't need to be replaced everytime a bulb is??

The unit is about 11 months old, and has been operating at 12hrs a day most of this time.

[Chris.L]

My lights and things are 2 years + old , working 8+ hours a day and have never been replaced?

[count_sexy_tart]

its recomended with all fluro's to replace the starter with new bulb to maximise the life of the bulb and there are only 75c to $2 depending where you get your bulb,i tend to go straight to the wholesalers

[Pegasus]

Hi Kriber,

Sounds to me like the starter more than the tube, as they usually turn dark at the ends when they are ready to pack up.

Try giggling the starter in its holder, as sometimes it's just a bad contact.

Also make sure the end fittings are well pressed onto the "bi-pin" ends, as they sometimes lose contact at one side which will give you that prob.

Still no joy....

Try rotating the tube slightly, as again, one side may be not touching the contacts correctly.

[Kriber]

Printed out Pegasus' post and went to work.

Final score Pegasus 1, light problem 0

Thanks very much Pegasus

The tubes are slightly dark at the ends, how dark do they go before they don't

[Pegasus]

Great to hear you sorted it

Tubes could last for months with the ends dark, but the efficiency will be greatly reduced, so... Mmmm.. for 15 bux or so (or whatever) you could just grab a spare tube when you have the readies

Got your PM

Cheers.

[Ira]

By that time they're probably putting out a LOT less light than new ones and the spectrum would have changed so you might as well replace them and get a brighter, better looking tank.

[Caryl]

It is recommended you change the fluoro tubes every 6 months (says she running tubes around 3 or 4 years)

[Pies]

Firstly I think you should replace you tubes regulary. Every 6 months for T12 (the big ols style fluros) or VHO fluros, and every 9 months for T8s (the slimer fluros), every 4 years for the T5s. These are approximations of course.

Not wanting to go into to much detail, but replacing bulbs is 'good', running old ones is 'bad'.

People always look at my freshwater and say "how do you get your plants to grow that well". I rotate my bulbs is a large part.

What type of bulbs to use? Here is me pleeding. When you buy a bulb, buy a useful one. So many people look at pet shop prices, and say 'no way', then straight down to Coreys (or any other electrical whosaler) and buy a cheap white light. This is not ideal. Some people get tricky and use a 'grolux' or 'grolight', this is worse.

Now pet shop bulbs are just far to expensive. And I can understand why people don't rotate their bulbs at this cost. So what can you do? Go down to Coreys (or whereever) and say "Kelvin".

They will know exactly what you mean. Most electrical whosalers stock different brands; phillips, sylvania, thompson etc. No-atter,just tell them you want a bulb in the 6000-6500 kelvin range, they will look at their chart and its all done. I buy a mixture of bulbs from Sylvania, $8 for the 6000k and about $12 for the 6500k from memory.

The white lights used in offices, and the red or yellow lights used in hydroponics or for growing seeds are not ideal for fishtanks. Kelvin measures the lights 'color spectrum', it has little to do with the strength of the light, or its brightness, its more the frequency of light. 6000-6500k is IDEAL for growing plants and retarding algae.

The lower the kalvin rating the yellower (then reder) the light, the higer the kelvin the bluer. My marine tank uses 6000k (natural daylight-ish), 10000k (blueish light, as seen deep under water). Also the higher the kelvin, the crisper looking the light, but the less intense e.g. a 10000k 250watt light puts out more lumens (brightness) than a 250watt 14000k light.

My freshwater uses 6000k & 6500k mixtures. My plant life is outstanding, my algae nonexistant.

There is some good advice here. GO FOT IT

Pies

[Kriber]

As the light wouldn't stay constant long enough to get the hood back on the tank (the slightest bump would send it flicking again) I went out yesterday to buy a bulb.

Bunnings biggest hardware store in Chch - couldn't see any 3ft tubes.

Riccarton lighting - 3ft only available in cool white, but they could have ordered 'daylight' ones in.

Mastertrade closed.

I ended up buying a bulb from the pet store. A Power-Glo 18000K (the pink one to replace the old one). Cost a bit but I plan to by a cheap 'daylight' bulb from a hardware store soon.

This new bulb really made a difference, the tank looks a like crisper and cleaner and I intend to replace the white bulb soon.

Can these 'pink' bulbs be bought from anywhere other than fish shops?

Whats the deal with 18000K bulbs?

Cheers,

Kriber

[Kriber]

Oh and thanks for that info Pies .

[Pies]

Kribber 18000 Kelvin would be blue, BRIGHT blue. I've seen 14000K very blue, and 20000k which is blue like a weilder. A 18000k bulb can't be red. You sure its not 1800k?

Ususally the red bulbs are very low kelvin (sub 3500, hence the redness) and are popular for growing seeds into plants for hydroponics.

The daylight bulbs you refur to should be in the 6000 - 6500k range, which is a daylight spectrum. Other kelvin light temratures are for artificial reasons.

Also just to confuse things, the colour can be manipulated by a frosting on the tube itself. I think one of the pet shop bulbs, the LIFE GLOW or something is a 6500k bulb with a sligh green frosting to give it a 'warmer' feeling, this is for asthetic reasons only, does nothing for plant life.

Pies

[Kriber]

It says 18,000 written across a capital 'K', must just be to confuse ppl. like 'cool change 100' orange drink (not 100% at all )

On the side of the box it has a figure showing

2800K Flora-Glo, 4200K Sun-Glo, 6700K Life-Glo, 18000K Aqua-Glo, 18000K Power-Glo and 'no number' Marine-Glo. Colours are reddish, yellow, grey/white, darker pink, lighter pink and blue respectably.

As long as it makes the tank look better I suppose :-?

[Ira]

What I've thought is, isn't the actual light created by phosphors on the glass luminescing when exposed to UV light created by the gasses in the tube? So, why can't they just sell a standard uncoated tube and you simply slip a sleeve onto it to produce the light you want?

Probably answer my own question, I guess it's cheaper and easier to put everything in one package, assuming seperating them would even work.

[MGilchrist]

Ira, as i understand it the phosphor coating reacts to the atmosphere, hence the implosion when you break one. also the phosphor degrades over time as do the elements in the ends of the tubes, so even if it could be seperated both parts start to degrade about the same time.

Have you seen an uncoated tube, they look cool.

[Dark]

i have one of the Power-Glo 18000K lights sitting above my 2ft propagating tank. the amount of growth that they stimulate is excellent but i have never had any luck putting them above tanks that are more that 1ft deep. I made the mistake of buying 2 of them to put above my 65cm deep planted tank; the light never reached the bottom.

I spent an hour or so talking to 'The Lightbulb Man' (Chews Lane, Wellington) yesterday. It is amasing to talk to someone who specalises in lightbulbs, i never thought there could be that much information to learn about the things.

An interesting point that he brought up: There are big factory places that make light bulbs. Someone like the people who make the Aqua-Glo will go in there and say 'we want x-thousand bulbs, print this logo on them and stick them in these packages'. Then another company will come in, and do exactly the same thing with exactly the same bullbs. As a result, as Pies mentioned, go down to a lighting/electrical wholesaler and order your bulbs by the Kelvin rating you want. TheLightbulb Man sells 4' 6500K tubes for about $15, the 10,000K tubes are about $25. Thats nearly half the price that Animates will sell identical tubes for.

I have been looking into getting light fittings from a supplier, Phillips 4' dual fitting is about $69 and reflectors are about $20. The same fittings are Coreys are about $80-90 without reflector.

Because places like Coreys base their prices on how much they sell of a particular item the 4' fittings have lower markup, the 2' fittings are the same price as the 4'. Guess i'll just have to start up another propagating tank

Another interesting point for those that know anyone who works for a city council: Those orange street lights are 75w Sodium bulbs, great for making plants grow and still small enough to think about putting in an indoor tank (i havn't gotten around to thinking that one through properly but i get the feeling a lot of cooling would still be needed). They have 25000 hour lifetimes.

Apparently the amount of light put off by a 6500K tube is about 3x its wattage, that reduces as the K rises. The nMH bulbs put off about 8x their wattage in light, and the Sodium bulbs put off about 12x.

And in other news; The fittings that I am looking at have solid state electrics and the only condenser utilising ones i can find are second hand. This seems to have something to do with the legislation preventing tubes with a certain amount of mercury being brought into the country, i think those bulbs require condensers whilst the new ones do not?

I'm still drowning in the vast sea of knowledge that is lightbulbs.

The main problem my tank is having at the moment is the lack of light at the bottom of the tank. We just raised the water level by about a foot after removing the terresterial plants and now there is a sufficient lack of light on the bottom of the tank to cause the high-light plants to be turning a sickly shade of yellow at the bottom whilst still green and healthy on top.

Certainly not helped by the port-hoplos trying to hide in them when the plants are fragile.

Oh, and i found this:

How does a fluorescent tube work?

A hot wire inside the tube sends out particles called electrons, which crash into atoms of mercury gas. The mercury atoms give out invisible ultraviolet radiation. The white phosphor coating inside the tube changes this into bright visible light. - GrindClub c/- Google

Rather like a TV/Computer Monitor, the gasses require low pressure and a lack of breathable atmosphere to operate in. I have no idea how the reduction in mercury effects this unless they have made the reaction more effective somehow.

I really have to stop talking...