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What’s the difference between Biohome Ultimate and lava rock?

While you can use lava rock as a decoration for your fish tank, it also comes with an added benefit of being a great biological filter. So, how does it compare to the Biohome Ultimate filter media?

You can find out in this comparison guide from Aquarium Blueprints.

Quick Summary

When it comes to biological filtration, Biohome Ultimate should provide a lot more surface area than natural lava rocks. These surfaces will be home to beneficial bacteria colonies that will remove ammonia, nitrite and nitrates from your tank waters.

The Biohome product also comes with trace elements that should help speed up the growth rate of these beneficial bacteria.

On the other hand, natural lava rocks are more aesthetically pleasing as you can use them as décor in your tank. Furthermore, these rocks are also a lot more affordable when compared to the competition.


The Biohome Ultimate is a lot more expensive when compared to natural lava rocks. You can check out the current price tags for both below:

Compatible Tank Waters

Both the Biohome Ultimate and natural lava rocks can be used in freshwater, brackish water and saltwater.


Each individual unit of the Biohome Ultimate is rather bulky with a measurement of around 1.5 inch by 0.5 inch. It is also brown with a noodle-like appearance. So, although you can put it directly inside your tank, Biohome Ultimate will most likely look very out of place. Instead, we recommend putting this media mostly inside a filter.

Natural lava rocks come in multiple colors, shapes and sizes. Therefore, you can add them directly as décor. You can also use the rocks as filter media although you will need to get smaller rocks to fit them in a media basket or compartment.

Ammonia Reduction

Ammonia comes from organic wastes from uneaten food or when you aquatic pets need to go to the bathroom. This nitrogen compound can be deadly to fish and other species.

To remove ammonia, you need to grow a bacteria that will consume it. This organism, which will appear naturally in your tank, will grow on all surface areas in your tank.

Both Biohome Ultimate and natural lava rocks provide a lot of density when it comes to surface area as both are very porous.

With that said, the Biohome Ultimate are manufactured to maximize its surface area, which means that it should provide consistently more space for the ammonia-consuming bacteria to grow on when compared to natural lava rocks.

Nitrite Reduction

When consumed, ammonia will turn into nitrite, which is another toxic compound that will harm your fish and other aquatic pets.

To get rid of nitrites, you need to grow a different kind of bacteria. Fortunately, this nitrite-consuming bacteria will grow naturally in the same environment as the aforementioned ammonia-consuming bacteria.

Out of these two options, the Biohome Ultimate should also provide more surface area than what you get with natural lava rocks.

Nitrate Reduction

When consumed, nitrites will turn into nitrates. While not immediately toxic, nitrates will stress out your fish at a high concentration. We recommend keeping nitrate concentration to below 40 ppm. If you have keeping more sensitive aquatic species, then it is better to keep nitrates to below 20 ppm.

In order to grow nitrates, you need surface areas that aren’t exposed to oxygen. Both the Biohome Ultimate and natural lava rocks feature microscopic chambers that offer little to no oxygen, making them a perfect place to colonize the nitrate-consuming bacteria.

You will most likely find more of these anti-oxygen chambers with the Biohome product, however, due to the way the filter media was manufactured.


Both the Biohome Ultimate and natural lava rocks require occasional maintenance to maintain effectiveness as biological filters. Otherwise, the pores will get clogged up, starving and eventually killing the beneficial bacteria colonies that consume ammonia, nitrites and nitrates.

For maintenance, we recommend that you rinse both products anytime you are doing a water change. You should use the tank water you are removing from your aquarium for the rinsing.

Trace Elements

The Biohome Ultimate comes with the following trace elements:

  • Titania
  • Alumina
  • Ferric oxide
  • Lime
  • Magnesia
  • Potash
  • Soda
  • Phosphorus pentoxide
  • Chromium sesquioxide
  • Manganic oxide
  • Zirconia
  • Hafnia
  • Zinc oxide
  • Barium oxide
  • Strontia
  • Stannic oxide
  • Sulphur trioxide

The elements will help beneficial bacteria grow faster on the filter media. These shouldn’t have any major impact when it comes to altering the pH and other water apartments.

Natural lava rocks should be completely inert as they shouldn’t leech anything in your fish tank.


As long as you regular rinse the Biohome Ultimate filter media and lava rocks, these products should provide biological filtration for your aquarium indefinitely.