Cant Remember The Rule....

[orange shark]

Is it atleast 1kg of live rock for every 2 gallons or is it atleast 1kg of live rock every 2 litres?

thanks, orange shark

 

[N1z]

Yup 1kg for every 2 gallons is correct. Or 1lb for every gallon of LR. But thats not to say you cant have more

 

[orange shark]

thanks! i thought id read that bt someone told me 1kg for 2 litres.

 

[SkiFletch]

thanks! i thought id read that bt someone told me 1kg for 2 litres.

Now that's a lot of LR

 

[I Love my fishies]

What is live rock? (please excuse my ignorance) and this in regards to a saltwater set up?

 

[SkiFletch]

Live Rock is rock that is literally harvested from the ocean. Sometime's its aquacultured or grown in "farms" behind the reef, but regardless, it comes from the Sea. It eventually ends up in your tank and brings with it beneficial bacteria, tunicates, beneficial invertebrates, macroalgaes, and even sometimes coral. Live rock is a natural reef's filtration, hence we saltwater hobbiests use it as well.

 

[I Love my fishies]

oh thanks for the info ... where do you source live rock I am about to do a fishless cycle with my new 4ft tank (once I get a stand for it) do you think using live rocks would be a good idea to establish the good bacteria? (for a tropical set up)

 

[orange shark]

live rock is for marine only (i think)

 

[SkiFletch]

live rock is for marine only (i think)

Correct. If you put live rock in a freshwater tank you'll have a rotting sespool within a matter of hours.

 

[Clarkii]

The rule is only a very loose guide for LR. I would always advise aiming at the bottom end of the ' rule ' to start with and build up. I normally aim for 1 Ibs of LR per gallon.

There is much to consider when setting up the tank, the amount of LR I think is to often over looked and people start aiming for 1kg per 2 gallons. Most tank volumes are often less than people think, internal dimensions often considerably smaller than the external dimensions when calculating volume. A good start is to get the exact internal dimensions and subsequently the actual volume of the tank ( where will the water line come to, not to the very top of the tank ).

Water flow and how this is generated and directed around the tank can reduce the amount of LR needed. Its better to have less LR working more efficiently than lots of LR with less than ideal water movement around and through it.

I know rules are an easy way to suggest amounts of LR needed but I find on the tanks I have setup is to aim low and increase later if needed. Quite often you will see what shapes you require to finish it off to such as a little Tonga branching rock to give it some nice structures. They other thing you have to consider is the type of LR you are buying. Indonesian and Fuji are far more porous than say Florida or Tonga which for the same weight have far less filtering capabilities than the first two.

Sorry to go on but I find such rules as the 1Kg per gallon as a very simple way of calculating something which isnt that simple.

You also have to consider the other filtration methods in the tank, I for one advocate the DSB. With the setup properly you would be extremely surprised at its filtering capabilities, with a well matured DSB I had less than 1Ib per gallon and no N03 detectable. This was a heavily stocked tank and a heavily fed one at that.

Hi by the way , nice site here

 

[Musho3210]

no NO3 detected could be caused by other things, not just the dsb. But if it works for you then i wont argue that.

Also live rock is limestone so it will buffer freshwater tanks and bring the ph up, you may or may not want that.

 

[andywg]

I normally aim for 1 Ibs of LR per gallon.

There is much to consider when setting up the tank, the amount of LR I think is to often over looked and people start aiming for 1kg per 2 gallons.

Umm, one kg per 2 gallons is the same as 2.2 lbs per 2 gallons, or only 1.1lbs per gallon.



I assume you meant 1 kg per 2 litres.

 

[Clarkii]

well not quite the same 1Ib per gallon = 2Ibs per 2gallons not 2.2 Ibs per gallon

Anyway I did mean 1Ibs per gallon, I was basing this on the rule I have heard many times which suggests 1.5 - 2 Ibs per gallon. Sorry I started waffling and couldn't stop

Just elaborating a little on the answer that's all.

I agree it could be other things in the tank sucking up the N03 but with only LR, DSB and an underpowered Skimmer on this particular tank I think the DSB is in the main sucking it up. Its a very basic system in regards to filtration but it works, the DSB was matured for 10 Months with the LR and lights in the tank before any livestock was added. I think the DSB is an amazing filter when working correctly.

 

[andywg]

well not quite the same 1Ib per gallon = 2Ibs per 2gallons not 2.2 Ibs per gallon

If you read, I said one kg per 2 gallons, is 1.1lb per gallon. That is correct to 2 significant figures.

The point I am making is you seem to feel one pound per gallon is a substantially different amount than 1.1lb per gallon (1kg per 2 gallons). You state that you feel one lb per gallon is a good point to start from (something I agree with) but you then bemoan people who start to aim for 1kg per 2 gallons. Once you convert kg to gallons you find that 1kg per 2 gallons is the same as 1lb per gallon.