Live Rock

[onux20]

My take on live rock. Two of the purposes, among several, it serves is to provide both biological filtration and hiding places for the fish. With the trend tending away from "rock walls", with nooks and crannies for fish to hide, sleep, and forage in; and toward "rock pillars" and "islands", that provide less than of the opportunities stated above; does one run the risk of not having enough rock work to adequately accomplish either adequate filtration or hiding/protection/feeding area for the inhabitants?

 

Has this trend lead hobbyists to increase dependence on additives, reactors, etc to manage water quality? Could the same/similar results be obtained with 10 more pounds of rock?

 

The high/random flow we all look to create in our tanks coupled with a lack of sheltered areas, will make for very tired and stressed fish. Wouldn

[Incredible Corals]

I would think that less would lead to much less filtration. In my case, I don't want a massive amount of rock in the display so I going to be filling up a refugium with rock. That way I get the necessary filtration but it's "hidden".

 

I would think quality of live rock is another factor. If you pull out 10lbs right of the ocean that is thriving with bacteria that would be much more sufficient than 50lbs of dry rock only cured for a few months.

 

In my tank I added 50 lbs of dry rock and then 30 lbs of live fiji to help seed the dry rock with bacteria it may never see without coming out of the ocean it self. I could be wrong but that is my thought process.

[Origami]

Keep in mind that it's not only the volume of the rock, but the flow around them as well. Some rock wall designs have a greater chance of having inaccessible dead spots where detritus can settle, thus adding a load to the biological filter. But I do see what you mean.

[Ryan S]

Two of the purposes, among several, it serves is to provide both biological filtration and hiding places for the fish. With the trend tending away from "rock walls", with nooks and crannies for fish to hide, sleep, and forage in; and toward "rock pillars" and "islands", that provide less than of the opportunities stated above; does one run the risk of not having enough rock work to adequately accomplish either adequate filtration or hiding/protection/feeding area for the inhabitants?

 

If you place the extra rock in your sump, as mentioned above, you keep the same filtration benefits, without cluttering the main tank, and being able to keep a pillar or island appearance.

 

As for hiding places/protection and stressed fish... Has there ever been a study done that somehow shows fish being less stressed with more rocks in a tank than not? And what do they need protection from?

 

I used to have the rock wall in my tank, and I never saw half of my fish or the inverts. When I removed the wall and just had a few small islands, I could always see my fish and inverts. I am not sure they felt any less protected or stressed, but I know I was less stressed because I could see the $100s of dollars of fish I had purchased for the tank.

 

Ryan

[GraffitiSpotCorals]

I like the rock "wall" look as long as you have caves, overhangs, and breaks in the "wall". I also think my fish like it better, the different variety and sizes we have need places to hide and feel comfortable. I don't think our fish would do well in an island style tank, while some do look nice. We just use 4" pvc fittings as base rock so flow is kept easier and fish have more space back there.

[treesprite]

I also expect to be able to reach every single inch of the bottom of my tank regardless of where my rock is or how it is set up, without ever having to move a piece of rock. That means I do not build walls, and I only put enough rock in the tank to fulfill the following functions:

 

filtration - it doesn't matter where the rock is in the system as long as it is there... some can go in the refugium or sump

 

coral real estate - the rock has to be set up to maximize the surface area of the rock without compromising aesthetics or fish needs.

room for fish to swim (also water flow) and places to call home - rock work needs to be "open", which means no rock walls. Towers do not maximize surface areas in most cases, unless rocks are very carefully cherry-picked. Building towers out of chunky rock is not, IMO, aesthetically appealing and doesn't give enough coral real estate (I have one large piece of rock that actually gives MORE coral space when standing up at a slight angle than it does horizontally). Caves do not create open space, and only have one way out. Fish can get trapped in them by other fish and panic due to being stuck in them. If you need to get the fish out from under them for some reason, you can't. I like archways because they give medium to large fish a sense of shelter while still maintaining open space and good water flow. Rock that has lots of natural nooks and holes is good for keeping smaller fish.

 

A person has to be very picky about purchasing live rock. You are better off picking up a piece here and a piece there over several months and paying $10 a pound for it, than getting a $200 batch of unseen $5/lb rock off the internet that when you take it out of the box you can't use half of it in your display because the shapes and sizes aren't conducive to your aquascaping preferences. I have rock from TFW, TL, BRK, Mr. C, and a couple hobbyists.

 

Also expect rock to break down, because after so many years it will. Part of the reason I'm having trouble aquascaping right now, is that a couple great OLD pieces broke apart. Who sells Manado Indo-Pacific that isn't an hour away from me?

Edited August 5, 2011 by treesprite

[trockafella]

. I am not sure they felt any less protected or stressed, but I know I was less stressed because I could see the $100s of dollars of fish I had purchased for the tank.

 

 

This a good point, I agree.!!!!

[zygote2k]

rock in the sump tends to get clogged with detritus due to less water flow. fresh rock has much better filtration capabilities than dry rock due to the amount of micro organisms. In my 60 skimmerless, I have about 40# of branch rock that is teeming with life.

It's not the amount of rock that you have, it's the quality of rock that you have.

[truestelf]

i agree its quality of the rock that matters not how much or how little you have.

[onux20]

i agree its quality of the rock that matters not how much or how little you have.

 

How is the quality of rock gauged?

[onux20]

rock in the sump tends to get clogged with detritus due to less water flow. fresh rock has much better filtration capabilities than dry rock due to the amount of micro organisms. In my 60 skimmerless, I have about 40# of branch rock that is teeming with life.

It's not the amount of rock that you have, it's the quality of rock that you have.

How long does rock stay "fresh" in a tank? I agree that "fresh" rock will initially have beter filtering capability than dry rock. But how long does that advantage remain?

 

Wont the dry rock eventually be populated by the same bacteria and organisms the "fresh" rock has?

 

Is it more important that you used "fresh" rock or that you have .6lb of rock per gal? If you bumped that up to 1 or more lbs/gal would that be better? I am not implying there is a magic ratio of rock to gallons, I am just asking the question.

Ron

[steveoutlaw]

As for hiding places/protection and stressed fish... Has there ever been a study done that somehow shows fish being less stressed with more rocks in a tank than not? And what do they need protection from?

 

 

I'm not really sure that a study is necessary. All you have to do is watch the behavior of the fish......when they get spooked, they go and hide. If you take that away then of course they are going to be more stressed. Someone must have researched it because on every website some of the fish care descriptions will specify "have alot of live rock and hiding places".

 

And I understand how frustrating it is to spend hundreds on fish and not be able to see them......probably almost as frustrating as it is to spend hundreds on fish and have them get stressed and die for lack of hiding places.

 

I guess bottom line is you have to research your fish to make sure that you are providing them with what they need. If you want less live rock in the tank, just get fish that don't require hiding spaces.

 

Just my $.02

[GraffitiSpotCorals]

I have a lot of rock and I see all my fish everyday. I don't think taking most of the rock out would allow me to see my fish better at all, but thats just my tank, everyones is different.

 

 

[davelin315]

I have a lot of territorial fish and I think that the only reason they don't fight more is because I have a "rock wall" in which they can establish territories and hide if they're smaller. I have arches and openings, though, so it's not the typical wall. In my case, I think that more is more - more opportunity to house diverse fish that would otherwise fight.

 

My fish include 4 tangs all between 8-10" (2x Dussumieri, 1x Unicorn, 1x Pacific Blue), a 10" Imperator angel, 2 Regal angels, a Powder Blue tang about 6", 2 yellow tangs about 5", and others. There's some aggression and a definite pecking order but they all have certain parts of the tank they can retreat to and hide in and there's only one fish that doesn't hide very well at night (the Imperator, although I think that's a preference for it).

 

So, in my case, more rock is better. I wouldn't go to the single pillars in my system unless they were absolutely huge and hollow.

[zygote2k]

How long does rock stay "fresh" in a tank? I agree that "fresh" rock will initially have beter filtering capability than dry rock. But how long does that advantage remain?

 

Wont the dry rock eventually be populated by the same bacteria and organisms the "fresh" rock has?

 

Is it more important that you used "fresh" rock or that you have .6lb of rock per gal? If you bumped that up to 1 or more lbs/gal would that be better? I am not implying there is a magic ratio of rock to gallons, I am just asking the question.

Ron

When you bring fresh rock from the ocean into your tank, the diversity of life will reach a point where certain organisms will outcompete the others for a food source and then there will be considerably less organisms that can survive in a closed environment. depending on your filtration system, this can be a relatively short time with skimmers and mechanical filtration. If you're running a natural system- no skimmers or mechanical, and use plant based filtration, you can see your live rock thrive for many years. I don't think there's any right amount of rock or weight per gallon either. There's simply too many variables involved- coral diversity, fish load, scavengers, detritivores, cryptics, etc. Then there's lighting and water flow- too much or too little will do harm as well.

As far as dry rock is concerned, it will only get populated by things that you introduce. Of course there's always the random chance that you'll get micro organisms introduced through the fish and inverts, but nowhere near the amount that you would have if you used fresh live rock.

[treesprite]

Just do what your livestock tells you to do. Dave gave a good example of why a person would do best to have a "rock wall" - I'd have never thought of it because I don't have a tank with those animals.

 

A fish often will make a hiding space right outside of the tank if it can't find one handy enough inside of the tank at the moment of flight.