[saltysteve]

Do old bulbs create extra or unwanted algae?

[Krazy]

its believed that when bulbs get old, the spectrum changes and some have said that it does indeed contribute to unwanted algaes.

[saltysteve]

hmmm well ive been getting some hair algae and brown algae. do you think it could be the bulbs? i dont think they are more than a year old

[Dr. Clyde]

I think your supposse to change bulbs at least once a year.

[Jeremy0322]

It depends on the bulbs you are using. I could be mistaken but you are supposed to change MH's like once every 6 months or something like that.

[saltysteve]

yes i am supposed to change them and i am but i just havent yet. they are mh and it is 6 months for a change over. i was just wondering if they caused the algae i have now. i didnt change them out yet since i really dont have much in the tank

[pogodzib]

The general rule for bulb replacement is 6 months for PC, 9-12 mo for MH and VHO, and 12-18 mo for T5. As bulbs age, their intensity decreases and they shift spectrums toward a couple colors that increases the growth rate of green algae. Old bulbs alone don't cause green algae growth since the algae needs nutrients (nitrates or phosphates) in the water to grow, but if the nutrients are in the water, the old bulbs can cause the algae to grow faster, which makes it appear that the bulbs are the problem, even though they are only a small part of the problem.

[bnhaus]

Yes, the loss of spectrum can cause algae to grow.

There are different opinions about when to change a light bulb.

I use a rule of thumb, 12 months. I change all the bulbs in the spring during the time change. Oh no, I have to change them this weekend.

Change the clocks, change the bulbs.

[Krazy]

Originally Posted by pogodzib

The general rule for bulb replacement is 6 months for PC, 9-12 mo for MH and VHO, and 12-18 mo for T5. As bulbs age, their intensity decreases and they shift spectrums toward a couple colors that increases the growth rate of green algae. Old bulbs alone don't cause green algae growth since the algae needs nutrients (nitrates or phosphates) in the water to grow, but if the nutrients are in the water, the old bulbs can cause the algae to grow faster, which makes it appear that the bulbs are the problem, even though they are only a small part of the problem.

WORD!

Good time-line on life of bulbs

Well spoken and I agree 100%

[Jeremy0322]

I was mistaken and am sorry for that, i honestly thought that MH's had the shortest life span of bulb. I guess you do learn something new every day.

[pogodzib]

Originally Posted by Jeremy0322

I was mistaken and am sorry for that, i honestly thought that MH's had the shortest life span of bulb. I guess you do learn something new every day.

That's why we're all here. The learn and pass on knowledge.

[Dr. Clyde]

I guess I should start buying bulbs now so I don't have to shell all the $$ out at one time when they are due.....in 11 months