How Often Do You Change Your Bulbs?

[Amunet]

Just wondering if it's about time to change the bulbs on our big tank.
Honestly, I don't think we've changed the bulbs in hmm, probably 2 years now.

How often do you all change your light bulbs/tubes in your planted tanks?

 

[Fishy friend2]

I don't know I don't change my bulbs until they go out

 

[StandbySetting]

When they stop working.

There's no real need to change them until they stop working, unless the output has dropped so significantly that it's affecting plant growth, but this is very unlikely.

 

[SuperColey1]

depends how into plated you are really.

If magnetic (electric) ballast (Most T8, T10, T12 and some T5) then yearly.
If electronic ballast (Some T8, Most T5, All T5HO) then 3 yearly.

Lamps on electronic (not electric) ballasts (will drop off significantly after 40% or so of their life (good quality ones, poorer ones maybe much sooner) So if a typical lamp lasts 20,000 hours that means change it after 8000 hours. That mean 1000 days @ 8 hours = nearly 3 years.

Lamps on electric (not electronic) ballasts flicker start which burns the lamp quicker hence the ends start to go black.

You'll know whether your ballast is electric or electronic by how the light starts.

An electric as above will flicker start. Change after 1 year.
An electronic will either start instantly with no flicker or it will be delayed. The delayed (programmed) start is the best for lamp life as it waits for the power to be there to start the lamp at a constant full power. Either way 3 years or so before any significant loss.

Andy

 

[Amunet]

Thanks for the info
So we should still be ok for a little while longer. Will probably start replacing them at the beginning of next year.

 

[Caprichoso]

When they stop working.

There's no real need to change them until they stop working, unless the output has dropped so significantly that it's affecting plant growth, but this is very unlikely.

I learned this too, after a decade of changing the bulbs like clockwork every 10 months ...now I have the same bulb in one of my tanks for almost 2.5 years with no ill effect to the plants. I do only have amazons, crypts, moss and anubias so I can't say how other plants would do in the same scenario.

 

[SuperColey1]

Ahhh.. Well neither you nor the plants will recognise the drop off. The plants will adapt with the slow decrease in output however when you replace them you are then hitting them with a big change. Its like going from low light to highlight in a day.

This is more the reaosn why planted folks change their bulbs. Because they change them before they drop too far below what they will be replaced by

Andy

 

[Caprichoso]

Ahhh.. Well neither you nor the plants will recognise the drop off. The plants will adapt with the slow decrease in output however when you replace them you are then hitting them with a big change. Its like going from low light to highlight in a day.

This is more the reaosn why planted folks change their bulbs. Because they change them before they drop too far below what they will be replaced by

Andy

That's interesting, so would that mean that when I do decide to change the bulbs that I'm going to have issues? If so, what would happen, a sudden algae bloom or just frantic plant growth? Or both, lol?

 

[SuperColey1]

You may get algae issues you may not. Just consider the word 'balance' is often used. This is often misinterpretaed.

Think of it like CO2. If you tinker with the CO2 too much it becomes unstable. The plants have to keep adapting their rubisco levels for the differing amounts and while they do that they utilise energy they should be using for growing properly. Algae steps in. Once you stop tinkering and the levels become stable again the plants start to fight off the algae.

So now think the same with the lights. You have 3 year old tubes on an electronic ballast. They are probably still giving out 90%. Therefore replacing the tube to a 100% is not a huge amount more.

Say they were on a magnetic ballast and are running after 3 years at 40%. You replace them and instantly you've more than doubled the light.

The plants that had gotten used to lowish light are now being pushed 2.5x faster than they were.

Whether this is in a non CO2 tank or CO2 tank this is a huge difference and not only will the plants have to adjust to the light. they may have to adapt to there now being a lot less CO2 available.

Now just because the electronic ballast statement above for 3 years says 90% doesn't mean it's a steady line.

Whilst studies say that good tubes (doesn't mean aquarium tubes) on an electronic ballast on average are still emitting 95% of their 'stated' manufacturers output after 40% of their life it doesn't study how quickly it drops off after that. Not many people are interested in this info other then us. Offices and warehouses do just as the guys above suggest. they run the tube till it stops. How low do you think a tube iis just before it stops no matter what ballast it is running on!!!

I dare say if a good tube has a stated life of 36000 hours then the reality is it won't really last that long. Maybe if it were to be left on for 36000 hours continuously however turning on and turning off of anything is likely to decrease its life so I say 20,000 as a conservative estimate.

Therefore if after 40% (8000 hours) it is 95%, that means in the remaining 60% of life it will lose the remaining 95% before failing.

So being very crude, untested and just making very guesstimated inaccurate judgements we can say that a tube will last about 8 years and be as a percentage as follows (I would guess the tube will just stop when it gets to 30% rather than going down further before failing)

Year 1-3 8760 hours =95%
Year 4 11680 hours = 90%
Year 5 146000 hours = 82%
Year 6 17520 hours = 71%
Year 7 20440 hours = 55%
Year 8 23360 hours = 30%
Year 9 = Fffffff - Off

So this is why you don't just run them until they burn out. We are using light to grow. Not light to see. If it is just about seeing then we can just leave them. As long as they are giving out light we can see. However if we want to grow and maintain things at a balance then we try and keep things at a relative constant

On a much higher scale than us imagine what would happen to a reefer who followed the 'run till they burn out' with corals in their tank. If for example the figures above were accurate they would be crying about how their one uber-succesful corals were now dying.

Andy

 

[Fishy friend2]

Do planted tanks need special lights

 

[SuperColey1]

Lights are lights.

Unplanted, nor planted NEED special lights no matter how much the the marketing blurb on the package or the chappie on a forum suggests

What I am trying to say above is not that people need to change lights at all. Just that some people are very serious about what they are doing and they want max efficiency. They don't want to be running and paying for X amount of Watts on their tank yet only having M output

So for all of us whether planted or not it is fine to buy good quality shop lights that will more than likely be equal or better than specialist aquarium lights for half the price.

For most of us it also means that we can run the lights as long as we want. As long as we can handle a minor problem of tweaking things every now and again and maybe dealing with a short algae problem.

Andy

 

[Fishy friend2]

That's what I thought the packaging is just different it does not matter

 

[SuperColey1]

Exactly as long as the bulb is good quality. Of course a $2 tube from the dollar store is not going to be as good as a Philips studio lighting tube. However the Philips Studio tube will most definately be better than most if not all aquarium tubes

Most aquarium tubes are pretty good quality however they are not the best tubes out there. More expensive than better non 'aquarium branded' tubes though

Andy