One treatment kills any algae of any species>


pico 1

It works, and you don't have to chase perfect tank params to starve the algae, the old school way that obviously doesn't work.

If you want to use an all natural method such as snails and water purification only to starve algae, then this isn't the thread for you.

But if you want all your algae dead by Monday so you can start fresh, then this is the thread for you.

The problems you will read with peroxide dosing come from adding it to the whole tank. There are about 10 better ways to use it, and these work 100% on any tank, so its the best algae remedy I have ever seen, in a decade of chasing a zero algae tank using every method ever written online in the forums.

The spot treatment:
drain your tank down for a large water change, preparing to match specific gravity and temp upon refill. wherever the algae is exposed, dropper a couple drops straight 3% peroxide right on the algae. let sit for 2 mins exposed, then refill the tank, the algae will die white by monday but more likely by the end of today, that fast.

the out of tank treatment
remove a problematic rock, and spot treat outside the tank if you can't or won't drain your tank, same outcome

cyano/bryopsis covered areas
use peroxide in a spray bottle, and use the bare minimum in sprays to cover the area, let sit for two mins outside the tank or in a drained tank, refill, problem gone.

The only downside to this method is that decorative macro algaes in the main tank can be wiped out, peroxide hates unicellular organisms (but not filter bacteria) so if you keep decorative macros only do the treatments outside the main tank and rinse well before installing, then it won't hurt the macro. Coralline can be bleached with peroxide, but who cares its only on the spot you treat it won't affect the other coralline.

here's a proof thread Im linking, with tons of before and after pics
Peroxide saves my Tank! With pics to Prove It! - Forums

The common bandwagon responses against peroxide use are:
-if you don't stop the source, it will just come back
-it will kill your filter bacteria

both untrue. Algae will always grow unless you take ultimate measures to purify your water and remove all phosphates and most or all nitrates, that's one option. The other option is to not headache yourself with all that, keep the water params within coral-growing params which basic water changes will accomplish, and spot kill the algae. In direct contradiction to that statement, my algae does not grow back faster. It grows back once every 3 months, and two drops of peroxide are worth the 20 seconds it takes to prevent algae for the next three months, its the best algae remover Ive ever seen and my tank is the cleanest its ever been.

The filter bacteria aren't catalase producers, they don't bubble in contact with peroxide (like the bacteria in the palm of your hand when you hold peroxide in it and it does nothing, those bacteria are unaffected by peroxide at 3% for the short intervals we use)

the bacteria in your ear that bubble are anaerobic catalase producers melded in ear wax, they are affected by peroxide, it is not a wide spread antibiotic as many assume, and its 100% harmless to your reef if used as a non systemic doser.

So, enjoy your algae free tanks its easy to cure any situation from string diatoms, to persistent cyano, in a way that actually works and doesn't rely on methods twenty years tested and inconsistent among tank keepers.

3% peroxide spot applied to any algae variant of any kind will kill it in one day, hows that for consistent lol

post before and after pics if you run it so we can start the proof here for this forum. Peroxide is the ace of spades you didn't know, I'll hang around to respond to any tests we can run to prove this.

here's simple proof, Reefmisers pics from that thread he said I could post. The peroxide gave him a fresh do over so that he could use more conventional methods to control its come back. The tank is running perfect so far, the peroxide did exactly what it is known to do when used as a spot treatment


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I have a problem with algae i beleive. it's about to drive me nuts.....check out my pic of my fish in the new fish thread in the fish forum. You will see what I got.
IMO, that is not getting to the root cause of the algea. Which is high nutrients. Also, are you removing the algea killed this way from your tank? If not, it will just decompose and feed more algea.

I would also be worried that the peroxide would kill any beneficial bacteria that is on the rock. It is an antiseptic used for scrapes and cuts.

It could very well be a way to kill the algea, but it will come back without proper aquarium maintenance. Such as water changes and not over feeding.
thats a common response but the physicality of actually doing it is different. In theory it seems like it would be like that I can see how...

already covered the filter bacteria part, its a spot treatment of one square inch with low residuals in the tank, plus peroxide has been used for fifty years in the freshwater aquaculture industry it is known that 3% diluted doesn't harm nitrifiers (same bacteria range filter fresh and salt water)

The point of the system is that water doesn't have to be perfect to maintain a perfect reef tank...low nutrient levels can still produce algae, but its at a slow pace, so burning it off once every two months doesn't make it increase faster, it just kills the algae.

The best way to prove the method is for someone who has tried algae techniques only to have them fail to post up before and after pics of a spot treatment. A key tenet in the thread is that the treatment is done outside of water, not in the main tank, so that remedies some of your concern.
the patches should be taken when they are this small, then it can't develop into what you see above.

If one ever sees patches like this, its proof the clean up crew is sleeping on the job as usual.


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Ok...none of those are really sound arguments. At best, the peroxide will certainly kill the algae, but why wouldn't it grow back if the conditions remain?

The conditions that lead to algae are often the same ones that negatively affect coral growth/color/health. The peroxide isn't getting rid of n/pho. In my opinion, it's treating the symptoms and not the disease.
my position is that you don't have to strive for low phos and nitrate, just keep it in the realm that corals need. Its so simple to keep a tank free of algae with occasional spot treatments that I found this preferable to meticulously chasing perfect water params.

In other words, my total work time spent on the reef is less with the peroxide than with chasing perfect water params, and it still coming back.

When people type that they have algae, but their tank params are low, people make a leap and say the algae is consuming all the nutrients, but they say this even when the algae biomass is relatively low compared to tank waste loading...the truth is algae can exploit even very trace amounts of phos and nitrate, so those two goals don't always produce an algae free tank.

Remember its not the same to disagree with something without trying it vs trying it and having a base to work from. I actively use it, peroxide will kill the algae and it will grow back at the same speed were we using tangs, clean up crews, sea slugs etc.
Peroxide is just another one of those options, an animal free approach.
another way to think outside the box with the stuff is to not use it continually. Like a UV sterilizer ( a great alternative to other algae treaments, they can be used in a reef with zero problems as well )

we don't have to run them all the time, just when there are problems. Same with peroxide, if one let the tank go and it looks like something from my pics, then a catch-up sure beats waiting for the mass to starve itself out and bleach, then any of the current methods can be employed to restore better export/binding/nutrient reduction.

a key factor in the post is that peroxide is something of an ace of spades, a specialty card when your other hands don't work.

In using peroxide to wipe off the front glass of my reef while it is drained for a water change, it prevents that green haze from growing whatsoever and in turn that prevents me from scratching up the front glass trying to get it off. Peroxide is a direct antagonist to old tank syndrome, its handy stuff for sure.
this one gallon vase is a very handy test subject for peroxide because it is so old and packed with coral. Any chemical insult would burn the tank savagely, but spot treatments prove to leave little to no residual left in the water after the dilution is performed following the burning treatment:


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I agree that the peroxide can have the same effect as the clean up crew - where the waste is basically recylced back in the system - without some form of nutrient export, the algae will stay in the system.

But, I still think it's important to try to eliminate the extra nutrients if possible.
agreed on the removal,

I use full water changes to keep my params at near zero.
its amazing algae still usually will even with low params. In most cases of successful long term algae treatment there is water quality and a form of manual removal or clean up crew

there's no way to numerate how many threads there are across forums where people are having algae problems with low water params regarding nitrate and phosphate, we needed something to add to just perfect water params.
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I dunno, I ran a fuge with lots of macroalgae and really didn't have much of an algae problem in my tank despite heavy feeding. Params often show zero or near zero with algae, because algae is extremely adept at pulling the nutrients out of the water column for their own growth. A lot of tanks with heavy GHA outbreaks show low phosphate.
I think there's a lot of promise in algae turf scrubbers as a positive form of nutrient export.
yes I agree about ATS, I follow santa monica's thread and think its fascinating how many people work in that line of algae control, there's so many ways to skin a cat.

Since most of my tanks are so small I don't have room for the occasional break-free clump to land/fruit in my front display, so it was easier to practice pure algae exclusion in my setups but if I had larger reefs an ats is a great system to keep dragonets and that's what Id have if I had fish~

ATS create unique zones of life and fauna for the tank, they are a fine alternate indeed.
How is it not killing off any of the beneficial stuff? Peroxide works by putting the area it is touching into an Oxygen rich environment. And most stuff is not meant to be in Oxygen rich environments. That is why when people are put on Oxygen tanks for health reasons that it is actually harmful to them as well.
If it was a powerful bacteria killer surgeons would use it to scrub in, they dont, its too selective on what it affects.

it can gargle in the mouth, and not wipe out the epithelium in your cheeks. if it did, or if it was a higher percentage grade, you would be open to getting infections by using it.

It works specifically on turf algaes of any kind, one treatment and it dies.
Rather than speculating, its better to actually try it with before and after pics like I posted, see if its legit or not.

In case there are any areas of concern, its why we are spot treating and not adding to the whole tank, those tiny spots don't matter, because Im running the test in the gallon vase and it would die much faster than you guys' large tanks.

Plus, across forums, I think Ive collected 100 before and after pics now and all have the same outcome, a perfect removal of algae with nothing bad to say in the matter.

Red tuft algae will grow in either high or low nutrient tanks, its substrate vectored pest, it does not come from airborne spores. Using peroxided (and fire from a lighter) are the top two ways of removing it, I wouldn't trust a snail although I saw the pics of the turbo eating the algae in that other thread.

There is no harm in using peroxide in the manner written, still waiting for someone to try a spot treatment with before and after pics, on any algae pest variant
You keep giving the example of the surgeons not using it to wash their hands. Which is fine and dandy, BUT, it is still an antiseptic. It is used for cleansing scrapes and cuts to prevent infection. Might not kill all the bacteria, but it does kill some. Where is you reference that it leaves the bacteria in and on the LR alone? How do you know it isnt killing that stuff?

Also, no matter what, IMO, you are still only treating a symptom and not the cause. You might make it look like your tank is healthy by removing the algea, but your water quality still might be sub par.

If you are doing this treatment in addition to proper maintenance, fine. But not as a cure all to algea in the tank.
What are you doing about the increase of H+ in your tank after using the peroxide? That will bring down the pH? I am not saying it won't kill algae but you need to be EXTREMELY careful when doing this procedure.