Texas Holey Rock sold as Live Base Rock at LFS in Minnesota

+1

Reef rock, being more porous, provides more surface area for the bacteria to colonize, pods to live / breed in, etc. Holey rock just doesn't have that. It doesn't take a science experiment or study for me to pick up, and look at a piece of holey rock and set it next to a piece of reef rock to tell that one is completely riddled with holes and weighs half the amount and would be able to support additional bacterial growth and amphipods, copepods, worms, etc.

 

What would be interesting would be to soak a piece of holy rock for a while, then break it apart. See how deep the water penetrates.

 

well said

 

I can tell you my 6line and blenny both sleep every night in holes in my TX rock. I'll get a pic of that tonight. They always sleep in the same spots.

There are other tunnels the fish can't get into that are perfect hiding spots for smaller fauna to live and breed in. I don't think your statement to the contrary is accurate in practice.

Bacteria are microscopic as stated... anaerobic bacteria can fit in TX holey rock pores just as easily as the pores of any other rock. They may be smaller in TX holey rock, but they're still giant from bacteria POV. the fact the pores on TX rock being smaller, in my mind, says it's a better anaerobic bacteria factory than typical rock.

I am focusing on the bacteria as the pro to holey rock (so the point I'm arguing, the macro sense isn't relevant (it is relevant to the tank, just talking about bacteria here)). You have a good point in that the rock is fairly smooth and doesn't have little crevices little brittle stars, etc. like. That is true.

When you're talking about aerobic bacteria - this is on the outside of the rock (more or less). The outside surface area of holey rock is greater than that of normal rock due to the holes. This is pretty clear to me.

The interior surface area (the pores), probably is less in a given volume of rock (I haven't measured, but I would be surprised if it wasn't too). But it seems to me it is better suited for anaerobic bacteria due to the density of it.

I think in the end, texas holey rock can support larger colonies of bacteria than normal rock.

The rest of the fauna - well, that's something different

Reef rock doesn't have more aerobic surface area than holey rock. not even close.

Reef rock does have more interior surface area (anaerobic bacteria), but the pores being as large as they are, probably have a higher ratio of aerobic bacteria than a given amount of holey rock will in the interior.

I think these two things (1. holey rock having more outside surface area for more aerobic bacteria and 2. interior surface area better suited to anaerobic bacteria) make it better at controlling ammonia/nitrites/nitrate than reef rock.

I do need a study to say otherwise.

 

Let me add, I do think it would take TX holey rock longer to mature to these levels than regular rock due to the density - but once it gets there...

 

Something to keep in mind is that the anaerobic bacteria cant live in the presence of O2. This means that all of the larger crevaces in the "real" live rock are actually reducuing the volume of rock that doesnt get O2. The water that soaks into the more solid sections of live rock is what the anaerobic bacteria is going to be working with. The area of the rock closest to the surface is going to be used by the aerobic bacteria as there will be O2 present.

Keeping this theory in mind that would mean that the "real" live rock is better at hosting bacteria that breaks down ammonia and nitrite while making the THR better at breaking down the nitrate. I say better because there will be more area's of the interior of the rock that arent close to the O2 saturated surface.

Either way about half my rock is THR and the other half is "real". I like both and think the diversity of rock types make for a better looking tank.

 

check out my new thread on crazy cheap dry base rock, this made my decision about ditching Texas Holey Rock very easy!

 

ha ha, no doubt! it would convince me too ;D

 

Very old threrd but interesting, no reason not to keep a good dicussion going for other people tyring to decide what to use to reference.

My main concern with THR is the density, which has been brought up. And although bacteria are microscopic, the main issue that has nto been brought up is can water flow bring the water and nutrients into the THR and can the clean water leave these tiny holes in an effiencent enough manner to help reduce nitrates?

Also has anybody since this was last posted in 2009 found any studies we can reference? The one guy here supporting the THR that does not have a fuge or an algae, how is your tank now a couple years later have you noticed any changes or had to do anything in addition to keep your nitrates so low? I would be interested to now how strong your powerheads are because I would imagine for such a dense rock, the issue with water exchange could be compensated for by having strong currents pointed at the rocks.