Dry Rock failure

[brad65ford]

Want to be as basic on this one since I could really go into details on some of my experiences but I have to ask in hopes I'm not allow.

We've been reefing for over 12 years with multiple different tanks with live rock from multiple oceans and also tanks with dry rocks / bb/ DSB/SB setups etc.. What I can't seem to figure out is if its just me or what but I always have more issues and failures in regards to coral success when the system is setup with complete dry rock.

Right now I have two different tanks one setup has been running for 7 months which is BB/dry rock and the other has been running for 3 months with live rock and also BB. The water conditions, water source,water changes and lighting are identical and the only difference is the rock one from the ocean and the other cured dry rock. Coraline algae is growing in both which IMO is always a sign the conditions are ideal for sps's. Now here is the kicker, I've been fragging most of the barely growing corals from the dry rock tank and installing them in the live rock tank and amazingly they take off growing successfully.

This difference has to be something real, something in the live rock that is giving off something that the coral like. My first thought is bacteria and or p04 reality difference since I'm already starting to notice the corals are becoming pale as the live rock have purged a lot.

Am i alone on this, or where did if fail along the way.

 

[glaukos]

hi brad

No you are not alone in this one buddy

Noticed the same thing in every tank i started,with dry rock.
But not in a long term.It just took the dry rock system a litlle more to become stable/mature/etc.
I always thought that a system which started with dry rock is mature after the one year mark.
Not something shientific to back this on,just what the tank and the corals showed me

In my humble opinion,the available bacteria from some brands are great in order to help a system that starts with dry rock.But live rock, is probably already "packed" with them so it has a head start advantage.

As for po4,many times,i found live and dry rock equally loaded with them and had to wait for some time or use different methods to get rid of them.

One of my biggest ?'s always where how much of all that bacteria or usefull organisms we want,come alive with the live rock that in many cases travelled a lot of milles without water.

 

[jda]

I write about this a lot. People laugh at me sometimes. I also feel that the man-made rock with the painted coating is also tough to succeed with since water doesn't penetrate it all that well.

The issues that I see it with dry rock is that it is full of dead organics that can be tough to get out of the rock... all the way to the center. This can take 2 years in some cases for the dry rock to be nuisance algae free and look like it is "mature."

After a while, the dry rock sheds all of the dead organics and gets populated with good things, but the rock can likely have bonded the PO4 and can be full, waiting to release - full rock is no good. I have never gotten live rock from the Pacific that had any kind of PO4 issues.

The crux is that your PO4 may never test high, at first since the aragonite of a new tank is bonding it.

 

[brad65ford]

There is some valiantly in this just not sure what or how its been proven. I've been fighting the clear bacteria slime in the dry rock tank for over a month how and losing most of my corals as the other take is just putting along like nothing is wrong.

Had and idea prove this by dropping is some live rock in the sump and see if it reverses the bad bacteria

 

[ausgus09]

If you're going to solely use "dry rock" in a tank, it is beneficial to at least start by almost suffocating it with something that has beneficial bacteria. From my reading, this process is sometimes referred to as "seeding", and the idea of it is to pile live rock or something like some chaeto all around the dry rock so that the beneficial bacteria growth on the rock can be extremely accelerated. Like jda said above, depending on the source of the dry rock, it can have a lot of "no good" stuff packed in it. Look into some freshwater curing processes to combat the die-off and after that load on the benificial bacteria. That's what has worked for me at least

 

[jda]

Way back when people used to use live rock exclusively, there were many solid anecdotes that the more porous rock, like Marshall Island or some of the deep water varieties, were better and processing N and harboring micro life to use the P and then up flow into the circle of life in the tank. Basically - the older the rock from when the coral died, the lighter and the better as it got more porous. I have not seen all of the different varieties of dry rock, but what I have seen is very heavy and not porous at all - this is my main gripe with man-made rock too.

I wonder if this factors in?

For a reference point, I have some rock from Marshall Island that are the size of basketballs that weigh 8 pounds... whereas the same size rock from Florida could weigh 20-30 pounds. Even at twice the cost, the MI rock was cheaper than cheap rock.

Seeding is not an problem. Your take can get all of the bacteria that it needs by putting in a fish or some other type of live rock or coral on a plug. It will quickly multiply and start to do it's job. The issue, IMO, is that it cannot do it's job very well in a bunch of plugged/gunked up dry rock.

 

[ausgus09]

Very good point jda, and I absolutely agree. I guess I made that statement considering solely the rock that is available in my area. I have three dry pieces that weighed in at 11 pounds, whereas if they were live rock they would have been well over 30 pounds. I'm not sure how relevant overall weight is compared to pourousity, but you almost have to assume that they are correlated. Nonetheless, it's safe to say that this is another one of those situations that completely depends on the individual circumstances... like almost everything in reefkeeping.
Butttt, I do think that proper seeding techniques can rapidly increase the rate of spreading the beneficial bacteria to your dry rock compared to just plopping it in your tank.