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What lighting changes will have a positive impact on the reduction of algae?

  • Reduce lighting period

    Votes: 119 32.0%
  • Reduce lighting intensity

    Votes: 45 12.1%
  • Reduce lighting period and intensity

    Votes: 84 22.6%
  • Program a "noon" burst of light (ie 3hrs 1.5wpg, 4hrs 3wpg, 3hrs 1.5wpg)

    Votes: 36 9.7%
  • Program a lights off "siesta" (ie lights on 5hrs, off for 5hrs, on for 5hrs)

    Votes: 33 8.9%
  • Change the spectrum/color temperature of lights

    Votes: 24 6.5%
  • I don't know: I never have algae! ;-)

    Votes: 31 8.3%

Is lighting the ultimate algae control?

73156 Views 73 Replies 44 Participants Last post by  Irida
Curious to know what people think...

Given that all your other plant nutrients (including CO2) are available to your plants in adequate (or more than adequate) amounts for your level of lighting, what lighting changes will have a positive impact on the reduction of algae?

Assume that you have let's say 3-4wpg.
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I am relatively a very new member but have been visiting this site very often. My aquarium has all the algae you can think of and also all other which you cant think of. I wonder how come my aquarium can home so many kinds of algae.
The water parameter seems fine to me. ph 6.7, GH 3deg, NO3 10 mg/l, NO2 negligible and water temp of 26-27 deg celcius.
The tank is approx 95 gallons and i am using two MH 150 watts each switched on for 5 hrs and there after two 18 watts osram fluora. for next 6 hours. I am using pressuried co2. The plants are growing very well but even better the far i have noticed black beard algae, green spot algae, dust algae, thread algae. theres another algae some what blk brown in colour and appears as small algae balls stuck to my gravel.
before i bought these MH i did my required reiki and came across with MH with ceremic techology and found their spectrum good enough for consideration. the spectrum were peaking in red and blue, 4200 k, 14000 lumens and cri of 95.
I am following estimative index for fertilisation which involves khpo4,kno3 and microsol-b.
Any one who can render some advise.

Tarun Jawa
Id be willing to bet that your co2 is too low. bump it up and get a drop checker. 2nd, with all that light your probably bottoming out your co2, stop using test kits and start dosing EI. 3rd, your tank should be heavily planted with all that light, at least until you get your algae in check. If you havent already get a bunch of cheap fast growers to get your tank under control. You should be dosing a pretty high amount of N and P with MH light and Press Co2.
All elements need to be balance to keep algae on check and lighting is only one of them.
I had algae issues in my main tank until went with a 6 hour photo period. I dosed ei and had pressurized co2 with a good substrate and 4wpg of pc light. If found out later that what my problem was my co2 measureing system, got a drop checker and that was fixed. My point is that IMO a shorter photo period will make up for other mistakes and keep algae at bay. I know am going to longer photo periods and seeing more growth. From what I learned most beginners should stay with a short photo period until things are well in control.
Somewhere along the line, I read that a seller of aquarium light fixtures replaced the blubs in the fixtures that he was selling to prevent the growth of algae. It was mentioned that 10000k grows algae so he replaced the bulbs that came with the light fixtures with 6700k.
I have two tanks. The one with 10000k grows algae. The one with 6700k is algae free. I do not use CO2, just Florish Excel & Seachem and lots of aquatic plants.
I have 2.5 w/g t5ho on my 55g and 30g goldfish planted tanks. I have some algae, GSA I think, but it's not an invasion, just on some of my plants and here and there on decorations. Today I started using Excel and I am waiting for my dry ferts from Green Leaf. Right now I use root tabs, flourish, flourish iron, Fleet enema and Epsom. I do 60% wc weekly on both tanks. New to this hobby(since Sept the 1st) and I love it. I vote for reduce lighting period, but as I said I am new to this.
Very old thread but still very relevant. I've been out of the hobby for a couple years because of moving so much but I'm finally settled and getting back into it. Figured I would toss my opinion in on this subject. I voted for noon burst, and to explain why, I'll just going to repost part of a conversation I had with WolfenxXx a few years back:

I feel like people are using far too much light for far too long. If I can make an analogy, it's like red-lining an engine every time you drive. You get to where you want to go quicker, but eventually that engine is going to fail. You may run out of gas, blow a gasket, throw a rod, burn off engine oil, crack the head, etc. There is a ton of problems that can come up if you are constantly running at very high RPMs in a car that was not designed to do so. Cars that were designed to do that, like F1 cars, have teams dedicated to maintaining them after every race or practice. It requires constant maintenance, and neglecting even one aspect will result in the entire system being unable to function. Similarly, I think with so many people using high light for eight and ten hours a day, it is almost a guaranteed catastrophe waiting to happen because of the constant need for maintenance. In many cases, this maintenance is specific to nutrients. I am not saying "no high lighting EVER," just in moderation. Similarly, it is good to almost red-line your car every now and then to blow out carbon deposits, etc. My bimmer gets red lined at least once a week (or near redline, at least.) My brother does the same on his Acura. I can also relate the lighting issure to weightlifting. If you lift hard for eight and ten hours each and every day, injury is all but inevitable no matter what supplements you add to your body. We grow while we sleep, and I think (I can't prove it unless it's already been proven) that plants do the same during non-photosynthetic periods.

I think a good discussion to start up would be the use of staggered lighting. Not the "siesta" BS that was all the rage back in the day, but better regulation/management of lighting intensities. Hopefully next year I will finally get my 50gal set up with a 24" Coralife Aqualight Pro HQI. That 2x65W plus a 150W HQI @ 10kK. That's a friggin ton of light!!! However, my plan is to run only one of the 65W bulbs for eight "viewing" hours (maybe ten depending on when I'm home) with the HQI turned on for maybe four hours in the middle of the day. Think about what happens in nature - the sun doesn't shine for eight or ten hours at maximum intensity all day every day. I do not believe high light = great plants. I think short bursts of high energy = great plants. If I'm not mistaken, Amano uses similar short, high intensity photoperiods on his tanks.
Of course, there are other variables involved but light is the primary. No light- no algae.
I think light is the main control for algae. From my experience, in places where the light is not present in the tank (ie under the shade of plant growth or under the aquascaping) THERE IS NO ALGAE.

so here is a true story from experience. i'm a college student. set up a planted tank at home before i left for school. came back thanksgiving to find that algae had completely ugly-fied and taken over the take. i cut off the light source completely. the only light came from ambient light from outside bouncing off my walls. lights out from one whole month. came back home during christmas. viola. no algae present. the plants that i did already have in there certainly weren't high-light plants (banana plant, java fern, java moss, anubias, rotola, microblade) BUT they all survived 100% and were perfectly healthy after the absent of light.

a few questions tho...
i've kept a saltwater tanks before too. one of the most important factors in determining coral growth/health and algae control was water flow. is that true for freshwater aquariums as well? do plants like circulation?

another question: how do you make ur plants GREEN? mine are of course green but they're never as green looking as fresh from the store or as some of your own plants in pictures
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Of course plants too love good water circulation, almost all tropical fishes and plants from rivers :)

But all algeas Depend on many factors. If high amonia, nitrate, phosphate. Then possibly better cover top of tank with lot of elodea, they suck all nutrients very fast and make good shadows for algea. And after then lower light intensity and shorten lighting period to some 8hr. My expiriments show, light must be constant, if make short on off periods, give more light for short period in day time period then there algea raise more.
Lower intensity and time period helps, but light need constant all day time period.
Also for me help with little nutrients dosage. Dose only Postasium (K2so4) and little micros, that necessary for plant survive and first sucked all phosphates and nitrates. And to much Potasium absolutely not harmfull, can dose always more as necessary.
I didn't actually read past page 3 so not sure if this has been mentioned but...
I've been maintaining a 6.8wpg "propagation chamber" for a little over 4 years. Lights are on 12 hours/day no matter what. The only time it grows algae is when I get lax on the ferts for more than a week or 2, and even then the algae only grows on the very bottom of the glass, hahaha like as far away from the light as it can get. You can actually see a line where the algae will not grow, as though it was cleaned all the way around the perimeter to 1/2 inch of the bottom or so. But as soon as I get back to dosing the algae goes away completely and it turns once again into the only tank that grows no algae!

Just a thought...
i'm a newbie, 2 months with a npt 10g. slow, steady growth of fur/string algae over the last 3 weeks or so. i got some floating frogbit that's multiplying like crazy; light is 23w cfl clamp light probably 8" above the tank; 5 hours siesta, 5 hours each in the am and pm. plants are doing well, but the algae just doesn't go away:mad: after reading this, i think i'll shorten the lighting day.
Im unable to vote. None of these options seem appropriate. Light is just another nutrient. Granted, making light the limiting nutrient seems the most important factor in algae control to me, it is not alone in controlling algae. All of the options other than lighting spectrum seem like they would work for controlling algae under the right circumstances. IMO its all about creating a situation in which the plants are able to monopolize the available light. So, "none of the above".
All elements need to be balance to keep algae on check and lighting is only one of them.

and just to paraphrase - what i believe is everyone's goal to control algae; "you want your plants to outcompete the algae for nutrients"

this is more likely to occur with vigorously growing plants; which is why people step on the light/co2/fertz gas pedal, rather than the opposite

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I voted "I don't know: I never have algae!" which isn't quite true its more that I never seem to get nuisance algae. I'm a bit of a nutter though and like to see just a bit of algae in my tanks (looks natural to me and feeds my fishes and inverts)
Curious to know what people think...

Given that all your other plant nutrients (including CO2) are available to your plants in adequate (or more than adequate) amounts for your level of lighting, what lighting changes will have a positive impact on the reduction of algae?

Assume that you have let's say 3-4wpg.
Reducing light intensity, due to a personal belief that it is a smaller shock to the system than changing duration of the photoperiod. I use floating plants for that. I actually cannot remember a time when I hadnt had any floating plants. Using only a DIY CO2 in a dirt tank this was a reasonable thing to do.
Plants will utilitize any color spectrum, its just that algae and the human aesthetics prefer those known as daylight this or natural that. Ive had 30+ aquatic plants in several tanks under different lighting conditions and all grew well and looked the same, when taken out of the tank. Maybe my opinion would change if I had used a microscope. :D Sure Ive never tried Rotala walichii and Toninas couse I have a hardwater tank, but HC grew well and slow even in a biorb with no WC and dosing at all under window light.
OT> As a lot of members suggested, light is just another nutrient. Id like to add there is no algae free tank, BUT tank maturity, and high oxigenation of the tank will reduce algae.
Oxygen is of utmost importance, not just CO2 levels. Beneficial bacteria will not benefit of CO2 but of O2, and that will have an impact od reducing ammonia levels and ammonia spikes.
Good water surface agitation is important even in an El Natural tank!
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