One treatment kills any algae of any species>

remember spot treatments are the thesis here, not systemic tank additions.

3% peroxide is antiseptic to a small portion of bacteria, not the majority, for the two minutes I listed as the spot treatment interval, proof is in the ammonia test.

The way you can specifically tell if its killing bacteria is to test for ammonia after use.

Test the pH after a spot treatment, it will not be affected. The way I know my water params are ok would be the sps plated all over the vase such that its becoming a problem lol

it makes no more sense for you guys to assume it kills everything it touches if you can't find ammonia to register and prove the bacteria is dead. we put it in our mouths and it doesnt kill all the tissue in your cheek, its weak to aerobic bacteria who already have to deal with it in their metabolic pathways and have a specfic enzyme ready to produce that degrades it (catalase, goog it)
the concern would be the systemic treatments, haphazardly dumping it into a tank.

If you have a spot of algae and want it gone, it may not mean your tank params are off. Test for them, in several cases including mine we see some algae growth even in the face of good water params. The peroxide is a fast way of burning that algae off, that's all the thread is about. There is zero impact to using a spot treatment...we have ammonia tests and pH tests if anyone wants to try it as well.
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I think where you will be most pleased are the tanks that have problematic red turf algae, and your magic turbos won't touch it. Getting turbos to consistently eat red turf is a problem, a real problem, its hit and miss. Same with mithrax crabs...but not peroxide.
If you have red turf theres not much you can do but physically remove it, it saved my tank from it, far more reliable than any snail but I was impressed how well that one turbo was munching that turf algae in the other thread
I think a similarity can be found in using UV sterilizers on reef tanks. Half the internet population says it kills good bacteria in the water and plankton and says they are bad, but the ones using them on their tanks don't notice coral starving, they notice less algae and it leaves them scratching their heads as to what's right. turns out we didn't need that plankton anyway, or we wouldn't have to feed our corals~ it was incidental, and sometimes worth the loss if it helped prevent crypto or algae/cyano. many good tanks run with uv, many without. same for peroxide, hopefully some cross verification of the spot treatment methods in this forum will show what the other forums Ive linked to had shown, a way to get the upper hand if you were having tough times.
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Generally speaking, if you have an algae outbreak, your params often ARE off. Again, I agree this can certainly work to remove some trouble spots of algae that just won't go away and can be a valuable tool. The danger here is people using it as a treatment to algae vs becoming better reefkeepers and managing their water quality better.
Generally speaking, if you have an algae outbreak, your params often ARE off. Again, I agree this can certainly work to remove some trouble spots of algae that just won't go away and can be a valuable tool. The danger here is people using it as a treatment to algae vs becoming better reefkeepers and managing their water quality better.

+ 1 Parrotchute. Its kind of like obese people that expect to take a magic pill and drop hundreds of pounds while continuing to sit on the couch eating fried fatty foods. The Peroxide might indeed kill the algae, but the algae grows for a reason. I had a horrid outbreak of cyano and after I was able to determine it was my old bulbs that caused the problem, the cyano went away.

Plus, for some of the nastier nuisance algae, spot treatment would be impossible, it takes over the entire tank (I know my cyano did). Now that my Nitrates and Phosphates are under control, I have almost no algae growth. What little algae I do have is destroyed pretty quickly by the Tang Herd
What would you say about the opportunistic hitchhikers that are not water quality based, yet are a source of headaches for many in the aquarium world:
red turf algae
string diatoms
hydroids (particularly for zosterae keepers)

all the GFO and new bulbs in the world won't help with those, peroxide will.

I have many tanks in my link list that have green hair algae even in the face of low phosphates and nitrates, plus you can find some in this very forum.

Additionally, small tanks that can't house tangs and assorted clean up crews will benefit from spot treatments, as algae are natural to the reef, its unnatural to not have algae. we will always have some residual organics and dissolved waste in any tank where we are feeding coral, and that can feed the algae, I disagree that attaining perfect water params is the only way to battle algae, but at least I provided pics and links for the evidence...quite a few success stories buried in there
For me the best success story is my own aquarium, it has been very simple to watch all good benefits and zero bad benefits from spot treatment use, so I showed up to give another the chance to find an easy solution to something we've been arguing about for decades lol, a fix to systemic algae. It is the most pivotal discovery Ive been shown in ten years, what it does for the stability and cleanliness of my tiny pico armada can't be understated, plus its all measurable with the specific tests mentioned.

at least we are getting some in and out on this thread, thanks for your input

I find it simply easier to spot treat every two months vs hook up all kinds of filters to attain sterile water, that's all, just another method that certainly works to keep handy.
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the philosophy of whether or not to use it still shouldn't take away from the original premise of the thread, that if you treat a spot any algae it will die, this is very helpful to know. Minus all arguments pro or con, the fact remains it works, with zero impact to the tank other than clarity and a start-over for algae so we can use one or more methods for the path of least resistance.

For the assorted algae problem threads here, striving for perfect water params and using grazers only isn't working consistently, its working sporadically, it is nice to have an equalizer method.
How can you spot treat stringy diatoms? They generally are not a localized plague.
Hydroids I can definitely see using peroxide on.

And the reason you think the GHA is growing in extremely low pho/no2/3 conditions is most likely because they are taking it up since they grow so damn fast, so it is not apparent in the water sample.

I agree it's unnatural to not have any algae. That being said, it's also unnatural for a lot of our corals, such as SPS, to coexist directly with nuisance algaes - usually the conditions they are found in are mutally exclusive.

Like I said a few times, I think it's pretty good to know this is an effective and safe spot treatment! I'd definitely use it if I had an area that was being stubborn and wanted the die off to push the captured phosphate into the water column where it could be dealt with via other filtration processes. But, if I had a algae breakout, I don't think it's a realistic or efficient way to deal with algae problems that keep springing up as a result of high phosphate.
sure that sounds fair, if I had high p03 Id be addressing that differently.

for string diatoms, a systemic is the best option and/or external treatments for indiv rocks in another container.

Systemic treatments won't kill filter bacteria either, peroxide has a 20+ year track record in fw tanks as a systemic, and we're all working with the same bacteria here.
there are careful doses for systemic applications we know will not cause a recycle.

For red brush algae, which does appear in spots, peroxide is perfect. The killing of red brush algae was the single most useful benefit I found in my tanks, and wiping the front glass with paper towel and peroxide bi weekly as a preventative for coralline and green haze.
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perhaps one agreement we can make is that grazers or peroxide have the same effect on recycling the original waste of the target pest...grazers=poop, peroxide=in-tank degredation of the original constituents of the pest

in fact peroxide makes no bioload, in that it may be better than grazers lol
somehow I left .Newman out of the pics credit for the thread. his are the zoanthids on page one. him and reefmiser created nice documentation of peroxide usage via pics and its instrumental in showing the benefit, not just saying it.

So for three weeks the spot I treated last with red hair algae has been barren, completely wiped out in two days.

It will eventually come back, but its not a problem now because it will be closer to september before I'll have to treat it again with one drop, its too easy now.

The best benefit of peroxide use I have found is the total confidence that no pest will ever take over my reef again, to me that's a pretty big deal.

not once in many years have I ever been totally certain red brush algae wouldn't wipe out my tank someday, but I am now
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