Sub-surface aerators offer a cheap, energy efficient, aeration solution for water bodies from the smallest aquariums to the largest lakes. But if they’re not paired with the correct end of line product (the bit that actually gets the air into your water), you could run into some issues. That’s why we’ve created this guide to airstones and diffusers so you can easily work out which option is best for your situation.

We’ve started off by explaining the key differences between the two, and why their output type is important. Then we’ve outlined the different varieties of airstones and diffusers available as well as how to install them.

We hope this guide helps you select the perfect product, but if you have any further questions, feel free to reach out.


Fine Bubble/Pore vs Medium/Coarse Bubble/Pore:

The first thing we need to cover is the difference between fine bubble/pore aeration and medium/coarse bubble/pore aeration. For the sake of brevity, from here on in we’ll simply refer to the different options as fine bubble and coarse bubble.


Fine Bubble Aeration:

Fine bubble aeration is the most efficient option for most situations. Since bubble size ultimately determines how much oxygen transfers into your water, fine bubble diffusion can provide superior results. This is thanks to their increased surface area and decreased movement speed which equates to nearly twice as much aeration capacity than that of a similar coarse bubble system.

Additionally, fine bubble aeration systems are far easier to install and maintain, which saves you time, effort and money. Where a coarse bubble diffusion system would generally require grounded anchoring (which means draining all your water before installing them) a fine bubble diffuser can simply be dropped into the water wherever you want it installed.

Pro Tip: Tie a buoy to your diffuser so you can easily find it if you ever want to pull it out!


Coarse Bubble Aeration:

While coarse bubble systems aren’t as efficient at aerating your water, they are great at mixing your water column. This is good for creating uniform temperatures and oxygen levels throughout your water body.

You will need to be mindful, however, that coarse bubble diffusers have larger pores than their fine bubble counterparts. This means that your system is at an increased risk of clogging and will therefore require more maintenance and upkeep to avoid damage to your compressor due to back pressure.


What’s The Difference Between Airstones And Diffusers?

Now we’ve gone over the different types of diffusion, let’s look at how those bubbles are delivered:



Airstones are generally used in smaller applications such as aquariums.

Material and bubble size vary, however our WaterTreats Airstones are crafted from glass bonded silica and produce an ultrafine bubble. This means that as long as they’re properly maintained they’ll outlive you and I. In other words, they’re ideal for any application.

One of the main reasons that airstones are generally delegated to smaller operations is that unless you have one capable of being used with self-weighted air hose (such as the WaterTreats ones we stock), you’re left to use aquarium tubing which floats around in a pond like spaghetti! This isn’t great for your aesthetics but can also pose a safety hazard, so it is best to be avoided.

Additionally, traditional blue aquarium airstones wear down over time which makes them quite costly in the long run if used in an intensive environment as you’ll need to replace them far more regularly.



Diffusers are most commonly used for ponds, dams, lakes and wastewater lagoons. In other words, dropping a diffuser in your water body is essentially the equivalent of pulling out the big guns.

You’ll generally have a larger compressor, you system will be a much more long term solution and you’ll see better results as you’re pushing a lot more air into your water.

Diffusers also offer a lot more diversity in their varieties which makes their uses far more flexible.

As with airstones, diffusers are made from varied materials and offer differing bubble sizes to match your aeration goals.



What Types Of Airstones And Diffusers Are There?



Airstones are a relatively basic product. Your options will mostly be based on size, material and fitting type. Our recommendation for this category is to ensure that your airstone is made from glass bonded silica and that you have an appropriate fitting to suit your needs.

WaterTreats Glass Bonded Silica Fine Pore Airstone - Aeration diffuser for aquariums, fish tanks and other small water bodies


Diffuser Discs

Diffuser Discs are one of the most common diffuser types. These versatile discs can be used alone or secured to a base and are generally crafted from plastic with an EPDM membrane.

The diffuser discs that we offer feature heavy duty construction and fine bubble EPDM membranes which feature anti-clogging technology.

Matala Fine Bubble Membrane Diffuser Discs - MD-225&310


Diffuser Hose

Diffuser hose is ideal for those who want to spread their aeration out across a horizontal area.

Diffuser hose can also be used to create aeration grids which are great for farming purposes. Simply connect your hose with the appropriate adapters and build your grid as large as you want (as long as you have a compressor that can deliver sufficient air).

We stock Matala 1/2″ Air Diffuser Hose by the metre and the roll, as well as both the 3ft and 4ft variations of the WaterTreats Bubbleweave Air Diffuser Hose.

Matala air diffuser hose


Tube Diffusers

Tube Diffusers are available in both weighted and non-weighted varieties.

The type that is best for you will depend on how you want to use your new diffuser. For example, if you want to be able to just drop your diffuser straight into your pond, grab yourself a weighted tube diffuser, hook it up to your aeration system, and off you go.

If you’re after a fancier system, however, you can get a non-weighted tube diffuser and connect it to an MDB base. MDB bases are the ones that most of our Matala Diffuser Discs sit on and your tube diffuser can easily be fitted to them with a simple T fitting.

Non-weighted tube diffusers can also be converted to a weighted design by simply filling one end with rock so you’re not locked into a set way of installation.

Matala Non-Weighted Tube Diffuser


Rod Diffusers

As the name suggests, Rod Diffusers are short rods that act as an efficient, end of line aeration solution.

Our Rod Diffusers are flexible and self-weighted and feature an eco-friendly, recycled rubber construction.

Matala Self-Weighted Rod Diffuser


What Else Do I Need?

Both diffusers and airstones will require air hose and appropriate fittings to function.

The majority of our diffusers and airstones come with the appropriate connections, however, air hose must be purchased separately.

Additionally, we strongly recommend adding a manifold to your compressor if you are using more than one airstone or diffuser. This will help balance out your air flow and prevent it from simply taking the path of least resistance and all coming out of whichever one is closest to the compressor.

Manifolds are also crucial for air compressors and pumps that will be operated in a shallow water body as they can protect your system from working too hard and becoming overloaded due to the environment.

It is also advisable that you include a check valve kit either in-line in your air hose, or just before your diffuser. This prevents water from flowing back through your diffuser and hose back to your compressor.

Matala Two (2) Valve, Heavy Duty, Air Manifold - 1/2 inch barb                  Matala Self-Weighted Air Hose


How To Use An Airstone:

Since they’re generally quite small and simple, airstones are often installed via a slip fit connection. Simply attach your aquarium tubing to the connection poking out of the top of your airstone and you’re good to go.

Larger airstones from the WaterTreats Glass Bonded Silica Airstone range can be attached to pond hose for use in larger water bodies. This is also done via a slip fit connection and you will be able to find connection size on the relevant product page for each airstone.

Please note that while all airstones available from Love my pond are self-weighted, there are varieties available for purchase elsewhere that are not. Non-weighted airstones will require addition steps for installation such as attaching weights or placing them underneath or within a weighted object.


How To Install A Diffuser:

Diffusers are just as easy to install, you just follow a slightly different process since they attach to pond hose not aquarium tube.

Depending on the type of diffuser that you have purchased, you may need to attach it to a base and/or weight it yourself. This will be clearly noted on the product page and the instructions that come with your diffuser will explain how to attach it to the base.

Tube Diffusers can be weighted with rock or alternatively, connected to an MDB base. For further information regarding attaching a Tube Diffuser to an MDB base, please contact us directly.


Is There Anything Else I Should Know?

Each individual diffuser or airstone will be rated for a specific LPM and CFM. These should be matched to your compressor and the output of your end of line aeration accessories should never exceed the output of your compressor.

As a general rule, this information for each airstone or diffuser can be found under the “Additional Information” tab of the product page.

You will need to assess the combined LPM and CFM of your diffusers or airstones to see whether they are compatible with your compressor. All multi-diffuser set ups will require the use of a manifold to ensure even aeration of your water body.


What If I’m Completely Lost?

Those wishing to avoid designed their own aeration system for their pond can explore whether the MEA Pond Pro 1 Aeration System is suitable for their needs.

If you have a larger water body and are unsure of how to create your aeration system, we suggest looking into the MEA Lake Pro Kits or contacting us for a custom spec system.

You can also get in touch with us via our contact page or on 1300 005 670 if you need some expert assistance.


If you have any further questions, feel free to drop them in the comments and one of our friendly specialists will get back to you ASAP.

If you’re ready to get started, head over to our shop page and select the components you need to design your aeration system. We’re here to help at any stage of the process and we’d absolutely love if you wanted to send some pond pics to so we can see your ponderful backyard oasis.