# Is H2O2 safe to kill algae?



## Taari (Nov 6, 2012)

I have this fuzzy light green algae/fungus/something crawling all over my viv's water feature and around the edges. I have used peroxide in the past sucessfully in my fish aquariums to kill algae, and it does not harm the fish as it immediately breaks down into H2O and O2 upon contact with organic material, but it was diluted by the water. Would it harm my frogs at all?


----------



## sanderdm (Jun 12, 2013)

Maybe this will help 

Hydrogen peroxide, either in pure or diluted form, can pose several risks:
Explosive vapors. Above roughly 70% concentrations, hydrogen peroxide can give off vapor that can detonate above 70 °C (158 °F) at normal atmospheric pressure.[citation needed] This can then cause a boiling liquid expanding vapor explosion (BLEVE) of the remaining liquid. Distillation of hydrogen peroxide at normal pressures is thus highly dangerous.
Hazardous reactions. Hydrogen peroxide vapors can form sensitive contact explosives with hydrocarbons such as greases. Hazardous reactions ranging from ignition to explosion have been reported with alcohols, ketones, carboxylic acids (particularly acetic acid), amines and phosphorus.[citation needed]

Corrosive. Concentrated hydrogen peroxide (>50%) is corrosive, and even domestic-strength solutions can cause irritation to the eyes, mucous membranes and skin.[60] Swallowing hydrogen peroxide solutions is particularly dangerous, as decomposition in the stomach releases large quantities of gas (10 times the volume of a 3% solution) leading to internal bleeding. Inhaling over 10% can cause severe pulmonary irritation.[citation needed]

Bleach agent. Low concentrations of hydrogen peroxide, on the order of 3% or less, will chemically bleach many types of clothing to a pinkish hue. Caution should be exercised when using common products that may contain hydrogen peroxide, such as facial cleaner or contact lens solution, which easily splatter upon other surfaces.
Internal ailments. Large oral doses of hydrogen peroxide at a 3% concentration may cause "irritation and blistering to the mouth (which is known as Black hairy tongue), throat, and abdomen", as well as "abdominal pain, vomiting, and diarrhea".[61]

Vapor pressure. Hydrogen peroxide has a significant vapor pressure (1.2 kPa at 50 °C[CRC Handbook of Chemistry and Physics, 76th Ed, 1995–1996]) and exposure to the vapor is potentially hazardous. Hydrogen peroxide vapor is a primary irritant, primarily affecting the eyes and respiratory system and the NIOSH Immediately dangerous to life and health limit (IDLH) is only 75 ppm.[62] Long term exposure to low ppm concentrations is also hazardous and can result in permanent lung damage and Occupational Safety and Health Administration (OSHA) has established a permissible exposure limit of 1.0 ppm calculated as an eight hour time weighted average (29 CFR 1910.1000, Table Z-1) and hydrogen peroxide has also been classified by the American Conference of Governmental Industrial Hygienists (ACGIH) as a "known animal carcinogen, with unknown relevance on humans.[2008 Threshold Limit Values for Chemical Substances and Physical Agents & Biological Exposure Indices, ACGIH] In applications where high concentrations of hydrogen peroxide are used, suitable personal protective equipment should be worn and it is prudent in situations where the vapor is likely to be generated, such as hydrogen peroxide gas or vapor sterilization, to ensure that there is adequate ventilation and the vapor concentration monitored with a continuous gas monitor for hydrogen peroxide. Continuous gas monitors for hydrogen peroxide are available from several suppliers. Further information on the hazards of hydrogen peroxide is available from OSHA[63] and from the ATSDR.[64]

Skin disorders. Vitiligo is an acquired skin disorder with the loss of native skin pigment, which affects about 0.5–1.0% of the world population. Recent studies have discovered increased H2O
2 levels in the epidermis and in blood are one of many hallmarks of this disease.[65]


----------



## petitpaume (Apr 10, 2013)

Try not to get it on the frogs directly, it is surprisingly toxic stuff... I don't know how well frogs are equipped to cope with oxidative stress, but it could potentially cause skin burns. Read an MSDS sheet on it, it'll shock you how little it takes to kill a pig/human with it.

If you're going to use it in the tank, I wouldn't use more than 5% H2O2, and I would pull the frogs while you do it. You should be able to put them back in fairly quickly (10 - 15 min), esp if the viv is a) warm, b) humid, c) exposed to strong light. Also, I would apply with a pipette rather than a spray bottle to keep it more localised.


----------



## TheCoon (Feb 8, 2011)

The hydrogen peroxide available at your local CVS or Walmart is a 3% solution. While it will most likely irritate the skin/slime coat of your frogs with direct contact, it shouldn't do any harm if applied in small doses to the algae and then sprayed down with water. As mentioned above it may be best to remove the frogs for a short period of time.

If you're working with stronger H2O2 then I'd caution against it. The 30% at work burns like hell when it gets on you

EDIT: basically said the same thing as the person above me...


----------



## Taari (Nov 6, 2012)

...yeah, I was just going to use the 3% stuff from the grocery store, that's what I've always used in the fish tanks.


----------



## diggenem (Sep 2, 2011)

I have also used it in planted tanks stocked with fish with no ill effects. It kills algae pretty efficiently.


----------



## fishman9809 (Dec 8, 2008)

H2O2 is very weak at 3% but is effective. I don't know how much it would harm frogs but it wouldn't be making direct contact anyway if you spot treat the algae with an eye dropper or something of the sort. H2O2 also decomposes fairly quickly in light and in warm temperatures. I'd feed the frogs to lure them away from the area and then spot treat so they don't accidentally stumble upon the H2O2 before it finishes reacting with the algae.


----------

