Why do old bulbs cause hair algae outbreaks?

FBNitro · 07/12/2008, 02:21 PM

I've read they cause them, just wondering the reason why.

My bulbs are 6 months old, and algae has just started showing up in the last month or so, might be related or might not be. I'm going to swap the bulbs just to be safe.

abulgin · 07/12/2008, 02:25 PM

Bulbs don't cause algae. Nutrients do. Of course, algae needs light to live, but if you have an "outbreak" it's not because of old bulbs.

kevin2000 · 07/12/2008, 02:28 PM

Not exactly sure why .. but I suspect the spectrum of the bulb changes as it gets older and that change tends to promote algae more than coral growth.

abulgin · 07/12/2008, 02:37 PM

Quote:

Originally posted by kevin2000
Not exactly sure why .. but I suspect the spectrum of the bulb changes as it gets older and that change tends to promote algae more than coral growth.

But even with a shift in spectra that is more friendly to algae, that wouldn't cause an outbreak. I would test your water, nitrates and phosphates in particular, to see where you are before blaming bulbs. What kind of lights do you use?

kevin2000 · 07/12/2008, 02:48 PM

Quote:

Originally posted by abulgin
But even with a shift in spectra that is more friendly to algae, that wouldn't cause an outbreak. I would test your water, nitrates and phosphates in particular, to see where you are before blaming bulbs. What kind of lights do you use?

Why I will agree that water quality is always a big issue ... lighting is just another food source for algae and the age of your lighting is a significant factor.

snorvich · 07/12/2008, 02:50 PM

What ^ he said. I would look at nitrates and phosphates first, always. As the spectrum of light changes on old bulbs, the corals may negatively react to it as well.

xJake · 07/12/2008, 03:02 PM

Lighting vs. nutrients is a very complex balancing act within reef aquaria.

As bulbs age they produce a residue on the inside of the bulb which reduces light output and slowly changes the spectrum of the light produced.

With these changes in the bulb the PAR (photosynthetically available radiation) decreases for the zooanxthellae within the coral tissue.

This process causes the zooxanthellae to use nutrients within the water column more slowly which in turn increases the amount of free nutrients within the water column over time.

These free nutrients are then available for algae to use for growth. With the change in spectrum in the bulb, PAR for nuisance algae then increases as the bulb shifts toward the red color spectrum. This is the cause of nuisance algae growth due to bulb aging.

These changes can be solved with simple techniques.

1) Move the bulbs closer to the water surface, this increases PAR and allows corals to keep growing at the same rate.

2)Increase nutrient export. Keep refugium lights on for longer periods, grow more macroalgae, harvest macroalgae more frequently, run GFO (phosphate remover), increase water change amount and frequency.

3) If none of the above options work then sometimes the only option is the change the bulb.

You can reduce/prevent this problem by turning on and off your light bulbs as minimally as possible, running longer lasting lights such as T5's or LED's, and/or decreasing the time your bulbs are on.

FBNitro · 07/12/2008, 03:15 PM

Yes, sorry I should have been more specific, I realize that it's unlikely my bulbs alone are causing an algae issue.

It's just that whenever someone posts about algae in non-new tank, everyone asks how old are the bulbs, and if it's > 6 months they tell them it's time to change them, implying (at least to me) that the bulb age affects the algae in a positive way from an algae growth perspective.

abulgin, my tank info is in my signature (80 watts PC). Phosphate is 0 (I assume all my other algaes/fuge is absorbing any I have, so reading phosphate is useless), Nitrates are 0.

Thanks for the response xJake, interesting info there.

abulgin · 07/12/2008, 03:19 PM

Well, the 6-month rule really applies only to PC and VHO. T5s and MH can last 12-18 months before they need to be changed.

I didn't mean to imply that light plays no party--of course it does--but if you are having an "outbreak" I would look first to something other than the lights--should have been a little more clear.

Sk8r · 07/12/2008, 03:31 PM

My mh sure doesn't last that long, however. I use a single 250mh and haven't had all that much experience with it, but I took one 12 months and had all sorts of problems before I changed out and really noticed a difference after. Hereafter, I'm looking at the bulbs at half a year, and the minute the tank develops a blush of something bad after that half year, I figure that's one thing to check early, along with other issues, like longterm accumulation of stuff, like need for more cleanup crew. No, it doesn't CAUSE it: but it's contributory.

07/12/2008, 02:21 PM	#1
FBNitro Registered Member Join Date: Nov 2007 Location: Vancouver, BC, Canada Posts: 641	Why do old bulbs cause hair algae outbreaks? I've read they cause them, just wondering the reason why. My bulbs are 6 months old, and algae has just started showing up in the last month or so, might be related or might not be. I'm going to swap the bulbs just to be safe.

07/12/2008, 02:50 PM	#6
snorvich Team RC member Join Date: Aug 2005 Location: Outlander Posts: 40,953 Blog Entries: 46	What ^ he said. I would look at nitrates and phosphates first, always. As the spectrum of light changes on old bulbs, the corals may negatively react to it as well. __________________ Warmest regards, ~Steve~

07/12/2008, 03:31 PM	#10
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	My mh sure doesn't last that long, however. I use a single 250mh and haven't had all that much experience with it, but I took one 12 months and had all sorts of problems before I changed out and really noticed a difference after. Hereafter, I'm looking at the bulbs at half a year, and the minute the tank develops a blush of something bad after that half year, I figure that's one thing to check early, along with other issues, like longterm accumulation of stuff, like need for more cleanup crew. No, it doesn't CAUSE it: but it's contributory. __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

07/12/2008, 02:25 PM	#2
abulgin Registered Member Join Date: Jul 2007 Location: Baltimore, MD Posts: 2,664	Bulbs don't cause algae. Nutrients do. Of course, algae needs light to live, but if you have an "outbreak" it's not because of old bulbs.

07/12/2008, 02:28 PM	#3
kevin2000 Registered Member Join Date: Jan 2004 Location: Portland, Oregon Posts: 3,805	Not exactly sure why .. but I suspect the spectrum of the bulb changes as it gets older and that change tends to promote algae more than coral growth.

07/12/2008, 03:02 PM	#7
xJake Registered Member Join Date: Nov 2006 Posts: 1,385	Lighting vs. nutrients is a very complex balancing act within reef aquaria. As bulbs age they produce a residue on the inside of the bulb which reduces light output and slowly changes the spectrum of the light produced. With these changes in the bulb the PAR (photosynthetically available radiation) decreases for the zooanxthellae within the coral tissue. This process causes the zooxanthellae to use nutrients within the water column more slowly which in turn increases the amount of free nutrients within the water column over time. These free nutrients are then available for algae to use for growth. With the change in spectrum in the bulb, PAR for nuisance algae then increases as the bulb shifts toward the red color spectrum. This is the cause of nuisance algae growth due to bulb aging. These changes can be solved with simple techniques. 1) Move the bulbs closer to the water surface, this increases PAR and allows corals to keep growing at the same rate. 2)Increase nutrient export. Keep refugium lights on for longer periods, grow more macroalgae, harvest macroalgae more frequently, run GFO (phosphate remover), increase water change amount and frequency. 3) If none of the above options work then sometimes the only option is the change the bulb. You can reduce/prevent this problem by turning on and off your light bulbs as minimally as possible, running longer lasting lights such as T5's or LED's, and/or decreasing the time your bulbs are on.

07/12/2008, 03:15 PM	#8
FBNitro Registered Member Join Date: Nov 2007 Location: Vancouver, BC, Canada Posts: 641	Yes, sorry I should have been more specific, I realize that it's unlikely my bulbs alone are causing an algae issue. It's just that whenever someone posts about algae in non-new tank, everyone asks how old are the bulbs, and if it's > 6 months they tell them it's time to change them, implying (at least to me) that the bulb age affects the algae in a positive way from an algae growth perspective. abulgin, my tank info is in my signature (80 watts PC). Phosphate is 0 (I assume all my other algaes/fuge is absorbing any I have, so reading phosphate is useless), Nitrates are 0. Thanks for the response xJake, interesting info there.

07/12/2008, 03:19 PM	#9
abulgin Registered Member Join Date: Jul 2007 Location: Baltimore, MD Posts: 2,664	Well, the 6-month rule really applies only to PC and VHO. T5s and MH can last 12-18 months before they need to be changed. I didn't mean to imply that light plays no party--of course it does--but if you are having an "outbreak" I would look first to something other than the lights--should have been a little more clear.