Pervious concrete

So I have been producing pervious concrete at our plant for the past few years. We have been making wave breaks and oyster reefs out of the material for use in the Chesapeake bay and gulf of Mexico. Our pervious mix was tested to be 97% effective at reducing nitrogen compounds (and that is even in oyster reefs which are EXCESSIVELY dirty!), and 45% more efficient than any other mix produced by other companies...

Now I have considered using this for our aquariums but am not sure about how "pretty" it will look. Has anyone heard of or considered using this type of mix in homemade rock? Google pervious concrete for pics if you are unfamiliar with the mix...

 

My first impression is that it will greatly increase surface area for bacterial growth as well as improve circulation behind the rock structure. As far as appearance, I really don't think it's that bad. It should definitely improve when it gets covered in coralline and corals.

 

The larger aggregate definitely improves surface area for bacterial colonization. I saw a pic demonstrating the right water content. The mix was formed into a rough ball shape and it really resembled Pukani rock. In my mind anyway. We know that Portland cement is acceptable for rock making, I just wonder what effects the fly ash, furnace slag and silica fume that's added to increase the durability would do in a closed system.
Might be worth looking into though because as Mr. Bill said, it would look great once it colored up.

 

We run straight Portland in most of our mixes... Really not a fan of the additional chemicals unless it's a super hot and humid day. All the fly ash or newcem would do is just make the already low psi even lower. I would probably run high air entrainment because that would give a nicer looking and slightly stronger product.