Use of Hydrogen Peroxide as a disinfectant treatment

[Onsan]

Use of Hydrogen Peroxide as a disinfectant treatment in the control of external parasites such as A.ocellatum, C.irritans and Brooklynella.

Applications:

1. 50-75ppm Bath for 30mins. Used as a disinfectant for newly acquired fish before adding to QT and DT.

2. 50-75ppm Bath for 30mins as a treatment for fish suffering from an infectious parasitic outbreak. Does not prevent recurrent outbreaks of A.ocellatum or C.irritans in an infected system, only provides temporary relief if returned to an infected system. Treated fish should be removed from the system and the infected system left fishless for a period no shorter than 28days in order to break the life cycle.

3. 50-75ppm Bath for 30mins every 3 days for a period no shorter than 28days. Used as a means of breaking the life cycle of parasitic protozoans such as A.ocellatum and C.irritans within an infected system whilst fish remain in the system. All fish within the system must be treated, regardless of whether an infection appears to be present.


Preparing a Hydrogen Peroxide Bath:

To achieve a 50ppm solution.
2 L of Water in a glass or stainless steel tank/container.
Add 3.4ml of 3% Hydrogen Peroxide
Add fish and maintain for 30mins
Do not aerate the water during treatment.
Return fish to QT or DT immediately as applicable.

To achieve a 75ppm solution.
2 L of Water in a glass or stainless steel tank/container.
Add 5ml of 3% Hydrogen Peroxide
Add fish and maintain for 30mins
Do not aerate the water during treatment.
Return fish to QT or DT immediately as applicable.

Please note, I've erred on the side of caution in my dosages preferring to use 50ppm/30mins as a general rule, many studies have shown longer and higher dosage rates are in common use and are effective. As this is relatively new in the aquarium industry and the effects on common aquarium species is unknown I have kept my dosages low. I initially trialled dosages of 75ppm which on it's first application on a severely infected fish seemed to cause some minor irritation, i interpreted this to be as a result of the density of open wounds exposed to the solution, on subsequent follow up treatments the fish did not show the same reaction.

Further potential applications lay in the control of Fungal outbreaks and external viral infections.

Treatment is applicable to both Freshwater and Saltwater pathogens.

Hydrogen Peroxide is an antibacterial, antifungal and antiviral and as such is NOT REEF SAFE. Treatments should be conducted in isolated baths.
It will kill algae, including coralline algae.

Hydrogen Peroxide is a caustic solution, it acts by oxidising cell walls, it is non toxic and completely breaks down to oxygen and water.

Evidence suggests that Hydrogen Peroxide aids in the the bodies natural immune system responses by signaling the convergence of white bloods cells resulting in a quicker healing process.

Hydrogen Peroxides oxidising reactions increase with temperature, higher temperatures require lower dosage rates, the above dosages were applied at 27C.

Links for further reading.

Research on the application of H2O2

Treatment of Catfish Eggs with Hydrogen Peroxide

Various Dosage Rates

Info on C.irritans and A.ocellatum Hydrogen Peroxide treatments

This is a relatively new treatment in the aquarium industry, however it is widely used in aquaculture especially in fish hatcheries where it is used in controlling pathogens on fish eggs, caution and user discretion is advised.

Make your own decisions on the suitability and application of this treatment, if you feel you cannot apply this with confidence you should seek more mainstream treatments as found on Reefpedia

[RyanG]

Hi Onsan,

I have just stumbled apon this thread- I have a breeding system that had 4 pair of clowns- in the last 24 hours have lost 2 pink skunk, 2 tomato and 1 clarki, and have one clarki and one tomato with signs of developing Broklynella I have just prepared a peroxide bath at 60ppm and have added one clarki and one tomato and will bathe them for 30 minutes.

I am planning the attack on the breeding system to get rid of the remaining brooklynella ciliates, would you reccomend leaving the fish in the system and bathing all fish every 3 days, i guess using the fish as an attractant for the disease to host on and then killing the hosts, or should I consider removing all fish and leaving the system fishless for the 4 weeks (as recommended elsewhere to remove remaining ciliates of the disease)?

Such a pain, but hopefully this peroxide method works for me!

[Onsan]

You hit the nail on the head, it really has to be either of the two options you mentioned. Yes you are using the fish as "bait" for the parasite, the are obligatory parasites - they must find a host within 48hrs or die.

Which one to choose? I guess dependent on the tanks you have available, if you had a parasite free tank that you could put the treated fish in and leave the other fallow you'd reduce the number of treatments required (and it's cost in $$$ and effort), if you don't then a 3-day treatment program will do the same job, just more work and peroxide used.

If the fish is severely infected, take particular care on the first treatment, with a heavy infestation more of the skin tissue will be exposed to the peroxide - it will irritate them more- better to end it early and repeat later if need be, on subsequent treatments you should find they show very little effects of the peroxide.

You could thoroughly clean and dry the system after a treatment to try to remove the cysts but there may be a chance that some of the cysts made their way into the filtration (which you can't clean and dry), and would later re-infect, i would think its a low risk but one none the less.

If you haven't read it already, check out the reefpedia page on it, there's some good info in the discussion page on other peoples experiences http://www.masa.asn.au/masawiki/index.p ... n_Peroxide

Let us know how you get on.

[seanluc]

I'm curious about this as part of a quarantine. Intend to put all new fish through the obligatory quarantine period but was uncertain about whether to subject them to hyposalinity during that period to get rid of ich that isn't symptomatic. This could be an alternative, but is it effective against parasites that are well established within the fish's tissues?

[Onsan]

the studies conducted so far have shown that is effective at reaching the protozoans embedded in the skin, however, the effectiveness of the treatment is subject to the dosage and its relative effects and tolerances of the fish. it has been suggested there may be some correlation to the thickness of the protective mucas layers evident in different species. Catfish for example can tolerate much higher concentrations, possibly due to their thick slimy layer protecting the protozoans beneath.
the inherent problem with relying on this method is that effective concentrations required to disinfect all/various species are simply not known. what may work on one may not be sufficient on another species, for the reasons mentioned above.

That being said, i use it as a precaution on all new fish added to my system, including on juvenile occelaris that i breed. I can not confirm that there was disease prior or after treatment but i use it as a precaution as i feel comfortable in applying it - i've never lost a fish to it - and feel that there is little risk to take but potentially great benefits.

my suggestion is to still use a QT (as you mentioned), this is only an additional precaution, and better to start with low dosages and treat a few times over the whole QT period increasing concentrations if comfortable.

[forsaken]

This might be a stupid question but where can you buy the peroxide and in terms of preparing to do a peroxide bath, the 2 ltires of water, I assume this is salt water?
Is it best to also have another tub of so water from your QT so once the 30 minutes is up, you can dip the fish into the water from the tank as a way of hopefully not transferring any of the peroxide into the QT?

[Onsan]

i use medicinal peroxide from supermarkets and pharmacies, comes in 3% and 6%.

I make my bath water from either the DT or HT, whichever the fish came from. Don't necessarily limit yourself to a 2L bath, use whatever is appropriate for the size fish, i use 2-3L for small fish like occies.
Just return them to the QT straight away, the limited peroxide left on after catching them would make little difference, it diffuses pretty quickly, the only residue in the QT in but a few secs would be oxygen.

[CheezotheClown]

You've mentioned to use either glass or SS. Is there a reason for avoiding a plastic tub?

Also have you had any experience treating infected fish or fish with bacterial infection using H2O2?

[Onsan]

I've noticed adverse reactions when using cheap plastic buckets, nothing that i can pin point but i believe there is the potential for the free oxygen radicals to act on the organic plastic, glass and stainless steel are inorganic and are effectively inert to the peroxide, safest bet to use inorganics so i recommended that.

yes, i would broadly class them as protozoan infections, not having a microscope to definitively identify them, i identified the cases to be irritans and brooklynella from their symptoms.
I have also used it successfully to treat fungal infections and i tried it on lymphocystis but can't be sure if it worked or if it just healed naturally.

[seanluc]

Not commenting on the general issue but ..

Steel - or more particularly its main component, iron - is far from inert to hydrogen peroxide.
Iron acts as a catalyst which greatly increases the effectiveness of hydrogen peroxide.
The process is called 'Fenton's Reaction" after the chemist who discovered it in 1894.
In addition to increasing the effectiveness of the peroxide as an oxidising agent, the reactions involved will also cause a rapid drop in ph.

Not sure how much effect the iron in a container would have as it is in elemental form as distinct from the ionised form it would be in in a solution.
However, I do know hairdresseers (who use peroxide routinely) never use metal utensils or containers with it.
Just thought its something you should be aware of.

[Rhys123]

Very well done Onsan a nice informative read.

[Onsan]

i use a stainless steel bowl, there is no reaction evident from the oxygen in the form of rust which would indicate oxidation, i think you'll find the nickel and chromium in the alloy prevents oxidation, that's the point of stainless steel, to be un-oxidisable.

DO NOT USE HAIRDRESSERS PEROXIDE, it contains other chemicals that will kill fish.

[dargonk]

Hi, thanks firstly for all your information so far.

From what I can gather I can uses a single bath in Hydrogen Peroxide, on all newly bought fish (At the lower end of course to reduce risk of negative reactions) that I purchase before putting them in QT to reduce the risk of itc etc problems later.

I just have a a few quick question

Where/what is the best source to get Hydrogen Peroxide for this uses from?
Any information on cost and potential problems with storage (ie will I be able to buy a bottle of this and then uses the same one months/year later still without side effects as I plan to only be buying single fish everynow and then, min 4 weeks apart)?
Also is there any chance you can provide a list of the fish that you personally have tested without side effects at the dosages you have listed.

Thanks

[seanluc]

Stainless steel rusts, it just rusts more slowly than other steel. There are different alloys passing under the name "stainless steel". For example, one grade for kithcen benches, another for fine cutlery, yet another for marine use.
Not all types of stainless steel are suitable for use with Hydrogen Peroxide.

Alloys which are suitable include 304L and 316L.

Even those alloys must be properly prepared:

Equipment fabricated of stainless steel must have proper surface preparation. It must also be chemically passivated prior to use with hydrogen peroxide. This removes surface impurities and creates an inert layer on the surface of the metal.

Without the inert layer, even stainless steel will react with H2O2. With it, it won't.

Properly passivated stainless steel provides a very stable surface for the storage of hydrogen peroxide.

Aluminium is a better surface, if you have any aluminium bowls lying around. However, High density polyethylene is also suitable.
In the long term it would become brittle, but that isn't a problem for short term use. A lot of common household plastic containers are made of HPE.

[Onsan]

Sean- like i said i use it and haven't had an adverse reaction with it, it is 316 s/s, i don't know what is involved with surface prep but considering the dosages used (20-175ppm) and the length of baths 30-45mins and the fact that in practice it hasn't caused a problem, i'm not concerned.
can you supply links/references to the quotes? i'd like to read more.
as the evidence of a reaction with iron would be rust and as my bowl is spotless, i'm fairly confident that there is either no or extremely limited reaction at best, and as the fish have not shown an adverse reaction when bathed in it, it suggests to me that whatever reaction may or may not be taking place, in practice, it is of no consequence.
the bowl i use is the same i used in the prawn hatchery i worked in, it's in the photos below.


Dargon, i've read food grade peroxide contains the least stabilisers and is reported to be ideal, i use medicinal grade from pharmacies and supermarkets and have been successful with that, they come in 3 and 6%, photo below.
The other materials i use are shown as well.

as far as costs, the small bottle is something like $4 and the large bottle (400ml) is $10 but twice the strength. i don't have anything to base this on but i believe over time (many months - year or more) that the relative concentration of stabilisers would increase as H2O2 is lost, maybe after a year donate it to the medicine cabinet? it's only $4, so it shouldn't break the bank having to replace it each year. sorry, can't offer anything definite there.

Fish that i've used it with;

occie clownfish, up to 75ppm-45min on adults and my fry up to 50ppm-30min from about 10mm long and up.
koran angel, 75ppm-30min
chromis, 75ppm-30min
lawnmower blenny, 50ppm-30min
mullet, 100ppm-30min
mixed estuary fish and banana prawns, 100ppm-30mins
corallimorphs, 100ppm-45min

a few months back i tested how far i could push a mullet, it died after 52mins in a 175ppm bath.
i use mullet, prawns and whatever mixed fish i catch in nets to feed my lionfish, i bath all of them initially when i get home in either 75 or 100ppm and again before i feed them to the lion (sometimes days after).

[seanluc]

If the iron is going into solution with hydroxyl ions it won't show up as rust. Rust is iron oxide and the relevant reaction is NOT oxidation.
I was not suggesting you would have any major problems just that you should be aware that catalytic enhancement of the peroxide's action is a possibility.
Something to consider in terms of dosage and effectiveness, that's all I was suggesting.
I'm not arguing with your method at all - just couldn't let the comment about steel being inert to peroxide go past without comment.
I'll chase the links down and post them for you when I'm at home again.

[Onsan]

well i don't understand it.
i spoke to my old man who's a boilermaker and he said no, not on 316. had a quick look on the net and found references to storing it in stainless steel.

Hydrogen peroxide should be stored in a cool, dry, well-ventilated area and away from any flammable or combustible substances.[36] It should be stored in a container composed of non-reactive materials such as stainless steel or glass (other materials including some plastics and aluminium alloys may also be suitable).[37] Because it breaks down quickly when exposed to light, it should be stored in an opaque container, and pharmaceutical formulations typically come in brown bottles that filter out light.[38]

that was taken from here: http://en.wikipedia.org/wiki/Hydrogen_peroxide#Safety

and there's this;

Theoretical rating (Cole Parmer)
Material Compatibility 10% H2O2 Compatibility 30% H2O2 Compatibility 50% H2O2 Compatibility 100% H2O2
304 stainless steel B2 - Good B2 - Good B2 - Good B2 - Good
316 stainless steel B - Good B - Good A2 - Excellent A2 - Excellent

taken from: http://www.ozoneservices.com/articles/004.htm

i read up some on passivation of metals and it seems that they use peroxide in combination with an acid to make the metal passive, by creating an oxide layer. new to me so yeah if you have any links i'd like to read more.

Keep in mind that the above is talking about concentrations from 10% and up, we're using 0.002 - 0.01%, very low levels of peroxide in comparison.

edit: ok, read some more, seems acid is used to remove any remnants of iron on the surface of the steel in order to ensure only alloys are exposed, peroxide is then used to ensure the alloy on top oxidises and protects the iron within, that suggests to me that peroxide actually assists in the passivation of the stainless steel as it facilitates the oxidation of the alloys.

edit: read up on Fenton's Reaction, haven't yet put it to the test but from what i can understand if there is any reaction with the Iron within the stainless steel it would become evident in a change in pH due to the the reactions:

Fe2+ + H2O2 ----> Fe3+ + .OH + OH-

Fe3+ + H2O2 ----> Fe2+ + .OOH + H+
http://www.lenntech.com/fenton-reaction.htm
Testing pH before and after the addition of H2O2 should indicated whether there is in fact an reaction with the stainless steel. I'll go home and test it tonight.

Edit: So i tested the 316 stainless steel against Fenton's Law with a 300ppm peroxide solution and the pH remained unchanged. So I'm happy to say that the is no interaction between stainless steel and peroxide at the concentractions employed in the treatment. As a further precaution it could be suggested to rinse a ss bowl with peroxide to ensure any iron that may be present is oxidised before treatment. Other than that i'm satisfied that ss is a suitable material.

Cheers! I learnt something from that.

[dargonk]

thanks for your answers. Looks like I'll try to track down some before my next fish purchase.

[Onsan]

no worries, and thanks to all for having an open mind and taking the time to read.
please take care when applying any new treatment, make sure you get the math right when mixing baths and above all else, stay with the subject during treatment, if there is any adverse reaction after a few minutes, return them to normal water straight away.

i have an excel (.xls) calculator that i use to calculate the dilution required if anyone needs it, i can't post it here so PM if you would like it.

an adverse reaction would be fish trying to jump out or trying to keep their head (gills) out of the water, obviously there will be some stress and excitement from being handled and dropped into a bath, i can't stress enough that keen observation is the best way to ensure you are successful. i usually cover the bowl with only a small section open to view them, to keep stress to a min while still being able to watch the fish.

[Dont ask me]

Great work Onsan, good to see you have a dedicated post for this treatment now, will be great to hear other people's results.

[CheezotheClown]

I have an P. navarchus or Majestic Angel in QT. She has been deteriorating over the past week (fraying pectoral fins) until yesterday where she parked herself against the skimmer pump (OR2500) and didn't move. She was alive but has started to show signs of infection with a white transparent/translucent patch on her body. I had very little time before work but I did have a 3% solution of peroxide on hand. As I had been following this thread closely I felt confident to try a 50ppm bath for this fish.

Mixing 6.75ml H2O2 into 4L QT water. 30 minute bath. The fish showed no signs of distress other than when it found itself in a net. The fish continued to swim circles in the bath for the 30 minutes. I have returned home a day later to find the fish more active but still showing signs of infection. She still takes food too.

My question is regarding method #3

3. 50-75ppm Bath for 30mins every 3 days for a period no shorter than 28days. Used as a means of breaking the life cycle of parasitic protozoans such as A.ocellatum and C.irritans within an infected system whilst fish remain in the system. All fish within the system must be treated, regardless of whether an infection appears to be present.

What is the basis for a three day interval? Is it as a precaution for a relatively untried process? Would it be wise to increase the frequency of baths given visible signs of infection?

[Onsan]

Thanks Cheezo, i'm humbled that you tried it.

The reasoning behind the 3 day interval was to develop a method in which the peroxide could be used to break the life cycle of a protozoan infection (like irritans) within an infected system. ie: the peroxide would disinfect the fish on the first treatment, but returning the fish into an infected system they would then be reinfected, by re-treating on the third day the parasites that infect the fish are not given an opportunity to mature and drop off to multiply.

Borrowing ATJ's lifecylce diagram you'll see that the parasite has a 3-7 day incubation period on the fish;


effectively, you are using the fish as bait to host the parasite and kill them before they can reproduce, continued over 28 days or more this would ensure that all parasites are removed before reproduction stage is reached.

As sufficient dosages have not been calculated for every species i would always recommend a precautionary follow up treatment, simply, i can't be sure that the dosage used killed every one of the parasites on the fish so i think it's better to err on the side of caution and re-treat the fish to be sure.

Do you suspect a particular type of infection? Any tentative diagnosis?

I have only treated a maximum of every second day, i'm not sure what effect a daily regime of treatment would have, though i would be cautious as i believe it does have a physical effect on the mucus of the fish, i would rather extend the treatment period rather than risk injuring the fish. just a gut feeling, no hard evidence on that.

When i treated my occie for brooklynella it took 3 treatments (each 3 days apart) before the film over her body disappeared, first treatment was similar to what you found, i saw only a minor change in external appearance but she perked up noticeably, a day after the second treatment and symptoms had retreated noticeably, by the time for a fourth treatment came it was pretty much gone with only a few wounds around her nose that were healing.

-----

on a separate note to all, like many other treatments, the main purpose of the peroxide is to combat an infection, although studies have shown it induces white blood cell activity on the wound(s), it does not help the healing process beyond that and certainly none at all once the bath is finished, a good diet and a healthy environment is very important to full recovery.

[CheezotheClown]

Thanks for the extra information

I've just finished a second bath. This time, given the reaction of the first, I've upped the dosage to 75ppm (10ml in 4L) and gave another 30 min. Again no sign of distress. In fact I think the fish appeared to become more comfortable as the bath progressed.

TBH I don't know what it is I'm treating for I don't really have any experience treating sick fish as to date I've lost a Flame in QT very rapidly to what I suspected to be Ich. I have also lost a Royal Gramma to something unknown whilst in QT and rapid deterioration too ie alive when I go to work and gone by my return.

I'll keep researching. The Majestic's infection is not as evident now in so far as an obvious white patch. She has lost over 50% of her pectoral fins and there is very minor fraying of the edge of her tail. Yesterday she had perked up considerably but today she went back to her catatonic state and itched when she did move.

My questions were aimed at maximum dose from the perspective of repetitive treatments. I think I may move to every other day.

[Onsan]

It sounds like it could be a protozoan infection of some sort, if the fish finds comfort in the bath it may suggest something is infesting its gills and the extra O2 is providing some relief from the symptoms. Treating it as tho it has a similar lifecycle may be prudent just in case.

I think you'd be fine with every other day at 75ppm, maybe back off when it improves, but for now it sounds like it may help get on top of the infection.

[CheezotheClown]

Just to update.

The Majestic's look and behaviour is improving. I'm maintaining a 30 minute, 75ppm bath every 3rd day.

Still no closer to diagnosing what it is though I do note that there is an amount of white/clear particles varying in size left in the bath after treatment. I've noted some dead scales in there too.

[ffallerken]

What about running two Quarantine Tanks in conjunction with the baths of Hydrogen Peroxide. Every 3 days, take the fish out of QT 1, and place into Bath and then from bath into QT 2. Wash out QT 1 and leave to dry for 2 days, then start it over again. Getting any parasites / issues out of the water of the QT has to be better than putting the fish bank into a possibly infected QT? Maybe this can reduce the time spent for a fish in QT after an outbreak?

[Onsan]

If you bathed them before qt you should have pretty much a killed them all first time around, but as a further precaution that could certainly help ensure none are carried through to the qt.

[JohnoL]

Hi Onsan,

Was passed this thread by a fellow reefer (in relation to my other thread query ich/velvet & cupramine),

I've got my angels and after reading this and attached threads, some H2O2.

So i understand everything correctly, 75ppm H2O2/30min will eliminate all ich/velvet - including those embedded under the skin - correct?
Does this mean, theoretically, once we get fish from LFS and treat with H2O2 bath, we could place straight into DT?

I've got a QT and assume it's got ich/velvet cos my last fish died in-situ.
Every 3 days i perform a 75ppm/30min bath for at least 28days (10 treatments), this is because the fish are returning to a potentially infected QT and i need to break the cycle - is this correct?
Do i need to wear gloves while handling the medicated water or are bare hands ok?
After 28 days, can fish go into DT? Or do they still have to go through a 6 week review period?
As i understand it, the H2O2 effectively "burns" the fishes skin - would it be worthwhile to dose QT with seachem stress guard to help them regain mucus layer?

Sorry for all the noob Q's.

Can you also PM me the spreadsheet you have?

Thanks.

[JohnoL]

Just to update.

The Majestic's look and behaviour is improving. I'm maintaining a 30 minute, 75ppm bath every 3rd day.

Still no closer to diagnosing what it is though I do note that there is an amount of white/clear particles varying in size left in the bath after treatment. I've noted some dead scales in there too.

Hi Cheezo, was wondering how your majestic ended up - was treatment effective?

[Onsan]

Hey Johno,

wow, no noob questions at all mate, you've got a pretty good handle on it as it is.

I would be confident in treating a reasonably healthy Angel at 75ppm for 30 to even 45mins, I would stress though the importance of staying with the fish during treatment to be sure of your fishes tolerance in its condition.
Your treatment plan would work as you described, its the right method for an infected system you can't clean, however I think it would be wiser to clean out the QT to rid it of cysts and reduce the number of treatments, the less you handle fish the better for them.
Can you transfer some of the water from the QT to a storage container or such, with the fish and some aeration while you clean out the QT?

You don't need gloves for the bath, the solution you'll make it from should be 3%, or 30,000ppm, and it's used directly on human wounds, the bath will be 75ppm, fairly mild in comparison. None the less, obviously follow instructions on the bottle and msds while handling the raw product.

you don't really want to burn the skin of the fish, you want to allow enough time for the peroxide to make its way through any damaged skin to the parasite beneath so that it can work its magic on them, treating the fish too long and at too high a concentration would damage the gills and suffocate the fish before it really died of burns to the skin as such.
While enough studies show that a once only treatment would do it, since we have the means to treat again reasonably conveniently, i think it's better to use a treatment plan and retreat appropriately to avoid a whole heap of pain from an infected DT if anything were to get thru.

If you keep the fish in the infected QT, treat for at least 28 days as you described and then transfer the fish (only, no water) to the DT.

As for the stress guard... sorry, can't really help, no experience if the product works or not or if it would after help after peroxide. sorry bud.
Good feed, minimal stress and good water quality is a good base to work from.

All the best.

PM'd.