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Do It Yourself Oxygenator
(I am happy to share this with everyone, but would love to get a little credit if you
re-produce this document, and would prefer you link to it instead.)
Hydrogen Peroxide breaks down into Oxygen and Water. If you can control this break down, the potential
is to provide Oxygen in it's purest form to your tank with very little expense and great results.
The use of this method to save fish during an electrical outage could prove extremely useful in the emergency
care of fish as well.
The benifits to extra O2 being introduced into your tank:
- Direct influx of O2 without surface aggitation which can cause CO2 loss
(important in planted tanks).
- Extra inflow of O2 for crowded tanks.
- In-tank diffusion of O2 in emergency cases, such as loss of electricity, without having
to directly dose Hydrogen Peroxide (a method sometimes used to prevent fish loss in a black out).
- Increased available O2 helps biological filtration in hard to reach areas (like gravel beds)
function better. This helps to keep a tank cleaner and helps to prevent anerobic pockets from forming
in the substrate.
- I am sure there may be benifits that I am not fully aware of.
- You can overdose with O2 if you are not careful, as with CO2, so careful monitoring is advised.
- Water can only hold so much gas, so if you fully saturate with O2, your CO2 may not be able to
disolve for plants. Though it would be very hard (if not impossible) to fully saturate water with this method.
- I am sure there may be draw-backs that I am not fully aware of.
The reaction of H2O2 into H2O & O2 causes heat. This heat (in the industrial pages) is said
to distribute easily into the water that normal H2O2 is mixed in, but it bears noting since strong
solutions of H2O2 break down faster as the heat increases. However, with the weak solution that is
available for home use, I have not noticed any heat increase at all.
I accidentally suffocated some fish while trying to reduce surface aggitation to hold in more CO2 for my plants,
so after reading a thread at
The Planted Tank about a fancy 'Oxydator' that uses a copper 'catalyst' (potentially lethal to invertibrates)
and a 'special ceramic' to break down Hydrogen Peroxide,
and costs a pretty penny, I got busy and did some research finding this:
Small amounts of other materials that contain catalysts (silver, lead, copper,
chromium, mercury, and iron oxide rust) can cause rapid decomposition and an explosive
pressure rupture of the containing vessel if it is not properly vented.
--- Product Information - Safety and Handling Guidelines|
Of course this was talking about industrial grade Hydrogen Peroxide safety, but it gave me several options for a catalyst
to break down Hydrogen Peroxide, one of which is already present in the plant and fish hobby.... lead.
I have been playing around with the correct ammount of this and that for a while to get a good
idea of how much O2 is needed, how much is produced, and how long it will produce, but I have the
basics of a good Oxygenator that I would love to share with everyone.
(It is also a lot cheaper than the $70+ for a fancy Oxydator)
- Small bottle (I used a little 8oz water bottle. Later I found that Juice bottles are more stable with flat bottoms.)
- Straight air line connector
- Drill with a bit that is just a little smaller than your air line connector.
- Air line
- Fine Bubble Diffusor (shown here with an old disposable undergravel kind)
- Innert rocks... only needed for 'in tank emergency' style as weight to hold it down (I used
glass decorative rocks, and glass marbles would work great.)
- Small piece of lead weight... or several weights if used for an emergency. (I used the kind
that holds down plants, but fishing lead weights would be fine as well.)
- H2O2 (Common Household 3% Hydrogen Peroxide)
1. Prepair the bottle...
If you are not sure how to make this set up, please read over this link and put the bottle together
the same way.
2. Add some glass rocks or marbles if it will go inside the tank to make it sink and keep it from tipping over
3. Fill the bottle 2/3 to 3/4 with common household Hydrogen Peroxide
4. Add a small piece of lead weight
5. Cap the bottle and place inside tank or put the airline/diffusor inside tank and place the bottle where it will not get tipped over
For regular use you can do it as an outside-the-tank system by running a longer air hose from the
bottle into the tank, but it would take longer for pressure to build up and pump O2 down the hose, so
the in-tank style may be better for emergency aplications.
Be sure to place your bottle in a possition that it will not get knocked over, or it will pump
Hydrogen Peroxide directly into your tank. A bubble counter as shown at the end of this
of this guide would be a good idea if there is any risk of the bottle being knocked over.
Shown 'In-Tank' Style with Tiny piece of lead:
I have been using a 16oz soda bottle with a 1cm x .5cm piece of thin lead weight
(commonly used to hold down plant stems) with a fine bubble undergravel diffusor stuck right under
my sponge pre-filter on my power head. The bubbles collect in the sponge and slowly disolve there.
So far it is providing a good amount of O2 to my 55 gallon tank filled with lots of guppies and shrimp,
and I no longer have to worry about suffocating my fish despite having almost no surface movement at all.
This set up has been going for well over 2 months and is still producing a tiny stream of bubbles.
After time, the lead weight becomes less effective from oxydization. I have found that by adding another small piece of lead after a month or two, more O2 will be produced again.
My tank has been cleaner and my fish, shrimp, and plants have all seemed healthier since I have started using
If you use the oxygenator in a case like mine (where I am depending on that little bit of extra O2 to keep
my fish healthy and happy in an environment with almost no surface movement)... I STRONGLY recomend using two
bottles started about a month apart, so that when one bottle is running out of Peroxide to break down, the other
is running strong. This will keep a more constant level of introduced oxygen and reduce the risk of ever
running completely out.
There are many ways to better diffuse CO2 bubbles into your tank water...
these can be used in the same way to diffuse oxygen produced from an Oxygenator.
- The best tip is to use TWO reactors and start them about 2 weeks apart. (Or a month apart for larger reactors.) This allows for a more steady rate of oxygen, since one bottle is getting going while the other is running out.
- If you have a place for it, you can attach your air line to a filter (usually canister type) to provide better disolvation of your oxygen.
- You can place your diffusor under your filter intake or flow in many cases to disolve more oxygen, but this may sometimes make certain filters rattle.
- A ceramic diffusor seperates the oxygen into super tiny bubbles that disolve more oxygen into the water before reaching the surface.
- A bubble-counter/trap can be made by the following method and can help keep peroxide out of your tank in the case of a bottle tip-over:
A few frequently asked questions from forums:
- Does the type of catalyst matter? Silver, lead, copper, platinum?
Normally, No... Some catalysts will break down the H2O2 faster than others, but there is really no difference than that as the metal should never get into your tank. Now this could be of some concern if the bottle tipped over and the water and H2O2 that was soaking around the catalyst was pumped into the tank. I sure wouldn't want copper soaked water in my shrimp tank or reef, so for added caution, I would not use copper as it is known to kill invertibrates.
- Could I use this to fill fish bags with Oxygen for transport?
While the result is pure Oxygen, it is a very slow production. This rate of production would take forever to even top off a fish bag, so I would say no. Though if you really have a few days to try it...
- Why not just use an air-pump?
While air pumps are great for most people, sometimes they just can't be used. For example, when the power is out, or when you are trying to keep surface movement to a minimum for a CO2 injected planted tank, or you live at 9000ft and have a tight fitted hood for your reef tank...
- Why not just buy an O2 tank?
For the same reason that I run DIY CO2. It is sufficent for my needs and MUCH cheaper for me to do. If your needs were much greater, like those with needs for preasurized CO2, then an O2 tank may be a good idea, but my needs are not that big, and my pocket book not that deep.
Write Up by Tally Fells