Live Rock

Freenow54 · Jul 11, 2021

Ok I was told no question is stupid. So I am going to try to disprove that theory. Can live rock function in fresh water?

Goaway · Jul 11, 2021

The life on saltwater rock will die off. But new life (mostly bacteria) from freshwater would eventually grow on it. Definitely not the same as saltwater life.

Miami Reef · Jul 11, 2021

Saltwater life is much more diverse (sponge, tube worms, coralline algae) but surface area in rocks provide the same benefits as removing ammonia and nitrite in both freshwater and marine systems. Using anything with surface area will give you the benefit of denitrifying bacteria.

Pistondog · Jul 11, 2021

Freenow54 said:
Ok I was told no question is stupid. So I am going to try to disprove that theory. Can live rock function in fresh water?

Good question. If you mean will live rock act as an accelerator in the nitrogen cycle? That would depend on the live rock bacteria's ability to survive in fresh water. Any life that cannot survive fresh water will perish. But can the nitrifying bacteria live in freshwater? I don't know.
In any case, eventually the live rock placed in freshwater tank will house the nitrifying bacteria, as will any other surfaces.

WheatToast · Aug 10, 2021

Also, you'd have to consider the calcareous nature of most marine live rock. Its pH raising properties make it unsuitable for most freshwater aquariums.

Righteous · Aug 10, 2021

As. noted above reef rock is made of aragonite and would cause pH issues in freshwater… especially planted tanks that use CO2.

But lots of other rocks are used in freshwater planted tanks, some mostly for decorative purposes. Lava rock is pretty porous and used frequently. I was always a fan of dragon stone.