Newby question.

[locoyo386]

Hi there,
To those who know the answear to the following question.
I have read that the rule of thum is 1-1.5 lbs of live rock (rock) to 1 gallon of water. Till this point I have not been able to conclude this figure. Can someone please explain to me how this rule came about, and why?

 

[hlcroghan]

I believe it came from trial and error for most people. It is usually the amount that people have found that gives the best filtration for the tank. You can always use more or less depending on what kind of tank that you have. If you have fish that like a lot of swimming room then you may need to cut down but if you have fish that need a lot of rock work then you may need to add more to make sure they are healthy.

 

[sickboy]

Can't give you a better answer than that. +1

 

[natclanwy]

Also depends on the type of rock, Caribbean farmed rock is very dense and heavy compared to Fiji rock so Caribbean rock will occupy less space than equivalent weight of Fiji rock.

 

[locoyo386]

Hi there,
Originally Posted by hlcroghan
http:///forum/post/2903599
I believe it came from trial and error for most people. It is usually the amount that people have found that gives the best filtration for the tank. You can always use more or less depending on what kind of tank that you have(So for what kind of tank is the range of 1 to 1.5?). If you have fish that like a lot of swimming room then you may need to cut down(Wont this cut down on filtration?) but if you have fish that need a lot of rock work then you may need to add more to make sure they are healthy

 

[natclanwy]

The amount of rock really comes down to personal preference, the more rock you have the more biological filtration your have. On the other hand though too much rock will decrease the amount of available swimming room you will have and it makes it much more difficult to provide adequete flow through the rock to prevent dietrus buildup. You need to look at what type of tank you want whether it be a reef tank or a fish only tank. Fish only tanks don't generally require large amounts of rock although the more the better but you still need to leave plenty of open space for swimming room if you are keeping large active fish, or if you are keeping reef type fish they will prefer plenty of rock to hide and swim in. Reef tanks usually have more rock to allow for more coral placements and to help keep the water quality pristine. Live rock plays an important role in nitrate removal, 40ppm of nitrate in a fish only tank isn't a big deal but 40ppm in a reef tank can be extremely detrimental to your coral.
In the end there really is no right or wrong amount of rock as long as you provide for the needs of your livestock. Add rock until you achieve the look you want and go from there.

 

[locoyo386]

Hi there,
Originally Posted by natclanwy
http:///forum/post/2904253
The amount of rock really comes down to personal preference(you are talking about the rock used in the display, which differs from the rock used for filtration, right?), the more rock you have the more biological filtration your have(is there a minimum amunt rock based on bioload?). On the other hand though too much rock will decrease the amount(of water column in the DT?) of available swimming room you will have and it makes it much more difficult to provide adequete flow through the rock to prevent dietrus(what is dietrus and where does it come from?) buildup. You need to look at what type of tank you want whether it be a reef tank or a fish only tank. Fish only tanks don't generally require large amounts of rock although the more the better but you still need to leave plenty of open space for swimming room if you are keeping large active fish, or if you are keeping reef type fish they will prefer plenty of rock to hide and swim in. Reef tanks usually have more rock to allow for more coral placements and to help keep the water quality pristine. Live rock plays an important role in nitrate removal(how important? I have read here that some people have more than 300lbs of LR and they are still having nitrate problems. Can you explain this further as to how, the specific amount of LR affects the Nitrate level?), 40ppm of nitrate in a fish only tank isn't a big deal but 40ppm in a reef tank can be extremely detrimental to your coral.
In the end there really is no right or wrong amount of rock(I agree with this statement) as long(as you are using the LR for specific reasons) as you provide for the needs of your livestock. Add rock until you achieve the look you want and go from there.
I do believe that the two main reason for using rock (LR) is to aid in setting up an ecosystem more suitable for fish and looks.

 

[natclanwy]

The rock in the DT provides the same amount of filtration as LR in other parts of your system the only exception being if you are using live rock in a wet/dry filter it probably does not provide very much nitrate removal as there will be very little anerobic bacteria present.
The amount of live rock can vary or you can go without entirely, the largest benifit to using liverock is its ability to support an anerobic bacteria population for nitrate removal, aerobic bacteria on the other hand will populate every surface of the aquarium and in addition some will be free floating in the water column also. So without LR you need to come up with another way to export nitrates whether it be through the use of a refugium, deep sand bed, or water changes. So again it comes down to personal preference on how much rock you want in your tank and what type of livestock you want to house, with the effects being more live rock equals less reliance on other methods of nitrate removal and vice versa.
The rock will decrease the amount of open area in the tank for your fish to swim in, if you are keeping wrasses and and psuedochromis that prefer to swim in and out of crevices and caves in the rock rather than swim in open water you could theoretically (not considering the other issues this would cause) fill the entire tank with rock and the fish would be happy and healthy, but if you were keeping Tangs or other open water swimmers they would be stressed and would not thrive in this enviroment.
Dietrus is basically waste and is generated from dying organisms, leftover food, and fish poop.
You are right one of the major reasons for using LR in your DT is to provide a more suitable ecosystem to support the fish and corals we would like to keep, but again it can be done without LR but it requires more maintence and the use of LR has greatly increased the success rate hobbiest have had in keeping many corals and fish.

 

[locoyo386]

Does anyone have any idea how much filtration can be provided, say in a tan gallon tank, with one pound of live rock (assuming that the rock has been cured and no more die off and it is somewhat established[not sure about this terminology]), that has only one 1" clown fish? The mechanichal filter would be a marineland 150 gph.

 

[spanko]

Too much variability in rock to answer this question. The more surface area the more area for bacteria to populate and the higher the biofiltration capability.
Natclanwy I have to take issue with your statement about aerobic bacteria in the water column though. In my reading "Your nitrifying bacteria do not reside in the water. Bacteria that cause disease do reside in the water, and will have a tough time living in a cycled tank’s filter due to biological exclusion. This also applies to the surfaces of decorations, and the inside of the tank itself. Ever notice the slimy feel to objects in a mature tank? This is the bacterial film, good nitrifying bacteria, that do create biological exclusion. This extremely thin film is multiplied many thousands of times over in your filter media."

 

[natclanwy]

Originally Posted by spanko
http:///forum/post/2905165
Too much variability in rock to answer this question. The more surface area the more area for bacteria to populate and the higher the biofiltration capability.
Natclanwy I have to take issue with your statement about aerobic bacteria in the water column though. In my reading "Your nitrifying bacteria do not reside in the water. Bacteria that cause disease do reside in the water, and will have a tough time living in a cycled tank’s filter due to biological exclusion. This also applies to the surfaces of decorations, and the inside of the tank itself. Ever notice the slimy feel to objects in a mature tank? This is the bacterial film, good nitrifying bacteria, that do create biological exclusion. This extremely thin film is multiplied many thousands of times over in your filter media."
You are correct a majority of the nitrifying bacteria is resident on the hard surfaces of the aquarium, but there is also a small amount of nitrifying bacteria that populates the water column, although not a significant amount and very little of the nitrifying process is completed by this free floating colony. This colony can sometimes be seen in a brand new tank where a large bloom of nitrosomonas bacteria will turn the water a milky white color. This can also occur during vodka or sugar dosing.

 

[locoyo386]

Hi there
Originally Posted by spanko
http:///forum/post/2905165
Too much variability in rock to answer this question. The more surface area the more area for bacteria to populate and the higher the biofiltration capability.
I was thinking about the above comment, and here are my thougts and questions;
The nitifying bacteria will colonize the rock surface for the most part, right?
How does the type of rock come in play (how does it alter this process?) during this colonization?
It is true that the more surface area the more room for the bacteria to occupy. How is this different in the the diferent types of rock? Also true that the more bacteria the more biofiltration. Does the bacteria grow at different rates in the different types or rocks?
At this point I aslo believe that the total amount of bacteria depends on bioload. A set limit of bioload will have a set amount of bacterial growth. They will even out to the point that you will not develop new bacteria, it will just replace itself. By adding new bioload you will allow for more bacterial growth, thus adding new bioload is also going to add new bacteria. We reah the bioload limit when the growth of the bacteria reaches a balance state. This is where the amount of surface rock comes in play. The more surface area you have for bacteria to colonize the more bioload you will be able to have. Thus the more rock the more surface area and the more bacteria.
This is where the rule of 1-1.5 does not make sence to me. You could have 1/2 lb of rock in a 55 gallon tank. Aslong as you understand how much surface area this will provide for bacterial growth. Thus understanding how much bacterial filtration you will have. This is what limits you to the amount of bioload you would have. I would find it very helpfull to understand how much biofiltration, a set amount of rock, can provide. It will help determine more accurately how much rock you should have based on bioload not water volume.

 

[robertmathern]

The different types of rock will not grow different bacteria. The different rocks are more or less dence than others. Now nitrate reducing bacteria resides deep inside your rock where oxygen is low. So the more pourous rock you have the more nitrate reducing bacteria you will have. on the surface of the rock contains a different bacteria. That bacteria turns amonia to nitrite then to nitrates. Then the bacteria deep in your rock turns the nitrate into carbon gas. Witch you get rid of through high flow

 

[locoyo386]

HI there,
Originally Posted by robertmathern
http:///forum/post/2912416
The different types of rock will not grow different bacteria. Not sure about this one, but with what I know so far I would agree.
The different rocks are more or less dence than others. One of the differences in rock is density, I agree. How does density affect the colonization of bacteria?
Now nitrate reducing bacteria resides deep inside your rock where oxygen is low. I agree. They also reside deep in sand beds, right?.
So the more pourous rock you have the more nitrate reducing bacteria you will have. I am not sure about this one can you explain further. I think that by having more pourous rock, you might have more oxygen reach deeper into the rock. Not sure though. So the more pourous the rock the more denitrifying bacteria you will have?
On the surface of the rock contains a different bacteria. The nitrifying bacteria, right?
That bacteria turns amonia to nitrite then to nitrates. Then the bacteria deep in your rock turns the nitrate into carbon gas. Carbon gas? Or is it nitrogen gas?
Witch you get rid of through high flow. Does it not escape into the atmosphere?

 

[robertmathern]

That bacteria turns amonia to nitrite then to nitrates. Then the bacteria deep in your rock turns the nitrate into carbon gas. Carbon gas? Or is it nitrogen gas?
Yep your right nitrogen gas. I was thinking of carbon at the time.
Witch you get rid of through high flow. Does it not escape into the atmosphere?
Yes it escapes into the atmospere through good gass exchange in your tank. To acheive that you need good flow or something churning the water at the surface.
So the more pourous rock you have the more nitrate reducing bacteria you will have. I am not sure about this one can you explain further. I think that by having more pourous rock, you might have more oxygen reach deeper into the rock. Not sure though. So the more pourous the rock the more denitrifying bacteria you will have?
True and false. Yes it will push air deeper into the rock but you have more pours in that rock that air cant get to. Not sure if you understand that.

 

[locoyo386]

Hi there,
Originally Posted by robertmathern
http:///forum/post/2912501
Witch you get rid of through high flow. Does it not escape into the atmosphere?
Yes it escapes into the atmospere through good gass exchange in your tank. To acheive that you need good flow or something churning the water at the surface.
Huh, this raises a good point. If you have buildup of nitrogen gas, and yoou have poor water movement, what happens to the nitrogen gas?
So the more pourous rock you have the more nitrate reducing bacteria you will have. I am not sure about this one can you explain further. I think that by having more pourous rock, you might have more oxygen reach deeper into the rock. Not sure though. So the more pourous the rock the more denitrifying bacteria you will have?
True and false. Yes it will push air deeper into the rock but you have more pours in that rock that air cant get to. Not sure if you understand that.
To be honest, no I do not quite understand this concept yet. I will have to do some research on this matter.

 

[cleve_seahorse]

Originally Posted by locoyo386
http:///forum/post/2912670
Hi there,
The nitrogen gas creates an almost smokey look to the top of the water.....not milky but smokey.... That happened in my first seahorse tank that didn't have enough flow....and denitrifieying bacteria are always in the deepest spots of pourous rocks and sand beds....they like dark , low oxygen enviroments....

 

[cleve_seahorse]

And the gas will continue to build up until you loose a few of your critters [ my poor 1st kellogis] until the problem is solved with LOTS of air lines , powerheads , filter surface areation etc , but that was on a hex tank....that was my lesson learned..The hard way

 

[locoyo386]

Hi there,
Originally Posted by Cleve_seahorse
http:///forum/post/2912719
The nitrogen gas creates an almost smokey look to the top of the water.....not milky but smokey.... That happened in my first seahorse tank that didn't have enough flow....and denitrifieying bacteria are always in the deepest spots of pourous rocks and sand beds....they like dark , low oxygen enviroments....
I have a question for you;
Does nitrogen gas occur during the nitrogen cycle (amonia, nitrite, nitrate)?

 

[cleve_seahorse]

Actually , it occurred after the cycle was over....no amm , no trites , 10 on trates but a slightly lower ph...7.6-7.9....after an extensive research I realised it was nitrogen gas....I got a test for dissolved oxygen and determined my problem and haven't had an issue since... I wish I had known what I do now....

Just a warning to those that see " smoke" at the top of the tank....it's not bacterial.. it's even worse....run more airlines