Explain Bacteria Load Using 10lbs. Versus 500lbs.

[427HISS]

I believe the old saying of using 2-3lbs of live rock per gallon. Say you have a 100g reef with 10 fish, if I add 100 more lbs. of live rock, why couldn't I add 50 fish ?

From what I heard, if you have enough bacteria that is sufficient in your tank, adding more live rock does not mean that 20 more fish can be added at the same time, the system will react better if you only add one fish per month.

Why does the bacteria need more time to catch up ?
Why not just add a bunch of more rock ?

I hope I'm explaining myself correctly,....

 

[Applegate]

I believe the old saying of using 2-3lbs of live rock per gallon. Say you have a 100g reef with 10 fish, if I add 100 more lbs. of live rock, why couldn't I add 50 fish ?

From what I heard, if you have enough bacteria that is sufficient in your tank, adding more live rock does not mean that 20 more fish can be added at the same time, the system will react better if you only add one fish per month.

Why does the bacteria need more time to catch up ?
Why not just add a bunch of more rock ?

I hope I'm explaining myself correctly,....

Here's my take on the matter.
Remember you have a closed system with a limited amount of water. Almost any amount of ammonia in the system will kill all fish. So the only way to keep fish is to complete the nitrogen cycle. Or at least almost complete it and remove the remaining nitrates. We use bacteria to do this obviously and bacteria is living organism that eats, creates it's own waste and reproduces. And you can starve the bacteria. Let a freshly cycled tank go with nothing in it for months and you wont have a cycled tank anymore. So with that being said, if you have a 100 gallon tank with 1 fish and 1000 lbs of live rock, your only going to have the same amount of bacteria as a tank with 10lbs of rock.

The bacteria will only continue to repopulate as long as there's is excess food(aka ammonia). And there is a rate at which the bacteria repopulates, it doesn't just appear.

So with that being said why not not just have 10lps of rock? Well the rock is only there for surface area so granted 10lbs of rock is plenty for 1 fish but if you eventually want 20 fish, you need more surface area.

And when it comes to adding fish, you're not limited to adding one at time neccessary, you just don't want to double your current bioload. So if you have 10 fish, you can easily add 5 fish of the same size and be fine. You just dont want to create so much ammonia that it becomes toxic before the bacteria turns it to nitrites and so on.

 

[Skydvr]

Housing fish comes down to more than just the ability to process waste.

You need to take into consideration swimming room for the specific fish in question, over crowding and stress, and aggression (amplified by over crowding) in addition to the waste buildup.

I believe that there are also hormones that fish release that ends up limiting growth rates. These will accumulate quicker leading to stunted and abnormal growth rates and patterns, if this does infact occur. I have read conflicting and inconclusive information regarding this, so I am not 100% certain that this does occur.

The nutrients/waste build up in waves when fish are fed. The rate waste is released isn’t constant, which would be easier for the bacteria to process. Sudden rapid spikes of ammonia shortly after feeding time followed by longer lulls of lower ammonia and nitrite between feedings.

There are things you can do to mitigate some of these effects, but you will go through larger quantities of media and will require larger filtration systems, but you will likely not be providing ideal environments for the fish and they will likely die early due to stress related issues (good luck dealing with an ich or velvet outbreak).



The inch per gallon, pounds per gallon, watts per gallon rules are extremely antiquated and really shouldn’t be used any more. When aquariums all had the same basic shape and proportions, they were a little more relavent, but with the aquariums available today, the advancement of equipment, and more importantly, the larger variety of livestock available (along with more information being readily available for individual fish species), the requirements of the individual fish in question is what determines what is appropriate. You can have a long and shallow tank that has the footprint of a tank 2-4 times the volume. This may be appropriate for a fish that swims a lot, but hangs out near the bottom while a tall tank with the same volume, but less than half the footprint would be completely inappropriate for the same fish, even if it worked out to half an inch per 20 gallons.

1 inch per gallon is not appropriate for a tang, which needs tons of swimming room, but is perfectly suitable for fish that hover around limited areas around their den (compatibility with conspecifics taking precidence for limiting the number in a tank). You can find information regarding recommended minimum tank sizes based on footprint or vertical swimming area.

 

[427HISS]

I've see a lot of tanks of late that seem to have minimal amount of rockscape, compared to reef walls, a lot started out as the dead white rock (not live rock taken from the reefs) that have a big to a huge amount of fish.

How can there be enough bacteria to handle those loads ?

 

[Applegate]

It honestly has less to do with pounds of rocks and more about surface area. Minimal rock work means in their sump they have marinepure or some sort of large surface area, extremely porous material. Bacteria covers just the surface of items so something like a sponge is going to have more surface area and therefore host more bacteria than say a pane of glass. So people with minimal rock work are really just supplementing their rock work with something else.

 

[Skydvr]

Sumps, porous ceramic based block/plates/cubes, algae scrubbers, media reactors, oversized skimmers, fine mesh filter changed/cleaned frequently.

Rock is only one part of the equation.

 

[427HISS]

That makes sense. Lets say you have one of the dead white rocks that has either been cycled with bottled bacteria's for a month and shows no ammonia etc, and another rock that has removed from a ocean reef. Wouldn't the latter have a lot,...more bacteria than the first mainly, because life not only is on the surface, but clear through the rock ?

Second.
I've only done a small amount of research on Marinepure, but some reefers for some reason, have had their system fail because the block bacteria crashed. Is that true or blame it on the hobbyist failed ?

 

[Cory]

You shouldnt add more fish simply because the tank will need more oxygen to support 50 fish and much more bacteria.

 

[tankstudy]

That makes sense. Lets say you have one of the dead white rocks that has either been cycled with bottled bacteria's for a month and shows no ammonia etc, and another rock that has removed from a ocean reef. Wouldn't the latter have a lot,...more bacteria than the first mainly, because life not only is on the surface, but clear through the rock ?

It all depends on how much food is available to the bacteria. It doesn't matter where its really from, it all comes down to whether the conditions meet the requirements to achieve high density bacterial populations. It can be in the wild or in a controlled system.

 

[Zohar78]

Second.
I've only done a small amount of research on Marinepure, but some reefers for some reason, have had their system fail because the block bacteria crashed. Is that true or blame it on the hobbyist failed ?

im still learning myself, only second year dealing with reef tank. i would think if given the same situation that caused the block bacteria to crash it would aso crash the rock/tank bacteria. now there was a situation i believe in some manufacture blocks where they broke down into "mud" because of mess up in the manufacturing stage. i wonder what effect that could have and possibly what caused it? as with lots of stuff, theres always pluses and minuses, to choices. either way, i plan on and i think most reefers would rather be safe then sorry and have too much capacity for biological filtration rather than little. i got a decent amount of rock in my 40 breeder, 30lbs worth, with extra 5 to 10 lbs in sump and also 1l of seachem matrix.

 

[427HISS]

Although some, of the great information that has been written is difficult for me to understand, but this is very interesting !
I have also read that a batch of block's from Marinepure had bad issues, so I hope they have that situation resolved.

I'm a old reefer from the 90's, and now we're back into this beautiful hobby. I'm in the process of building a in-wall 125g mixed reef. It faces the livingroom and the back side is in the office/Parrot,.... old bedroom.

Back in the 90's I made a bottom plenum under a deep sand bed using 2" pvc stands, egg crate the window screen on top, in our 75g reef, very much like Alf Nilsen\Jaubert's plenum filtration system. It worked very well, with no nitrates and very low phosphates with a pretty high fish load and feedings. Too bad that we did not test it out for long period of time, but we sold out to go sprint car racing. I'm surprised it's no longer used.

Anyway, I have a lot of original reef rock from our other tanks and a lot of the dead white rock from BRS. I really don't know how I will mix them together and look nice, and how much to use ? To have the rock as minimal display, where ''less is more'', should I have a tank for added amount of rock that is plumed into the sump ? I'm asking because of knowledge and if,... we want more fish than you'd expect in a 125g. Not saying we will, but it can be a learning curve from you guys.