removing nitrates with live rock?

[quiet reef]

I've had high nitrates, 20 - 30 ppm. Tried lots of methods to reduce them. With large frequent wc I've got them under 20ppm. I thought that more live rock might help since I had maybe 20lbs in my 150gal. Yes, not much, I know. So brs finally had the tonga shelf w base pieces in stock. So I bought 35 lbs of that plus 10 lbs of pukani. I put the rock in another tank w just enough water to cover the rock. I set up a power head to run a canister containing carbon, ceramic rings, and a sponge (very course). I used the water taken from my display when I did some water changes. Figured why waste salt and rodi water to cure rock. Then I decided I better get more rock so it could cure together. 50lbs of figi from brs . The rock will be for my 150 and my 120 when i get it set up. They will run off of the same sump. Before I added it to the curing tank I tested the water to see where it was at. It still had some nitrite but no nitrates:eek1: I was quite surprised. The water I put in there started w 20 to 30 ppm nitrates, now gone. Did the rock really process the nitrates into n2, or did they absorb them? Some of the rocks are quite large, 20 " in diameter and 3" thick. I've read about the 1 to 2 lbs per gallon, so I knew I needed more rock. Has anyone else seen this much reduction so quick? It's been just over one week. Thanks.

 

[bertoni]

[welcome]

If I understand correctly, you've been curing the rock for about a week, and the nitrate level in the curing container now is zero, even though the water used for the container is measurable. The rock can't absorb nitrate, so I'd guess that either the test has failed or the rock has processed the nitrate.

 

[Aquarist007]

What test kit are you using to measure nitrates?
How long has the 150 gal been established and how is it stocked.

 

[quiet reef]

Thanks Bertoni! I retested display and curing tank to verify results.
Thanks Capn! I am using simple tetra strips for nitrate and nitrites. Waiting for my red sea pro nitrate test kit to come in. I expected nitrates to rise after organic matter on rocks decaded. Surpised that they were gone so quick. The 150 gallon has a black clown, blue damsel, and a blue tang. As well as 2 dozen hermits, lots of snails, brittle star, and 2 urchins. It has been running over a year.

 

[bertoni]

You're welcome! Good luck with your tank!

 

[Aquarist007]

Thanks Bertoni! I retested display and curing tank to verify results.
Thanks Capn! I am using simple tetra strips for nitrate and nitrites. Waiting for my red sea pro nitrate test kit to come in. I expected nitrates to rise after organic matter on rocks decaded. Surpised that they were gone so quick. The 150 gallon has a black clown, blue damsel, and a blue tang. As well as 2 dozen hermits, lots of snails, brittle star, and 2 urchins. It has been running over a year.

If it's been running over a year you could add 10lbs a week directly to the tank

 

[Ontheway]

I have a little question here, does coverage of corallin algae negatively effect bacteria housing capacity of live rock? if yes, how seriously? I am experiencing nitrate problem (around 50) also, and relating it with corallins over live rock since I have 3 snails and 3 conchs in 30g. As far as know, rock itself do not leech nitrates to water.

 

[kegogut]

The general rule of thumb for live rock is 1lb. per gallon. I myself have about 300 in my 220 with plans to have over 600 lbs. when I get my 220 sump set up.

You could always check Clist for people selling rock as well. You might have to acid wash it but thats very easy and will save you lots of cash if your setting up a fairly large system.

 

[Aquarist007]

The general rule of thumb for live rock is 1lb. per gallon. I myself have about 300 in my 220 with plans to have over 600 lbs. when I get my 220 sump set up.

You could always check Clist for people selling rock as well. You might have to acid wash it but thats very easy and will save you lots of cash if your setting up a fairly large system.

Experience has taught me not to operate by "rules of thumb" every system is different

 

[Ontheway]

Experience has taught me not to operate by "rules of thumb" every system is different

Captain, do your experinces include curing some of the existing rock pieces to enhance their hospitality to bacteria? (or, swap an existing rock with a similarly sized LR or DR)

May be the actual question here is, how long it takes for a rock piece (and its bacterial flora) to start processing nitrites and nitrates (latter by anaerobics) ?

 

[kegogut]

Experience has taught me not to operate by "rules of thumb" every system is different

Indeed,thats why myself am going to try to include as much LR as possible. I'm going to have around a 450-500 gallon system with 600-800 lbs. of LR,maybe more but at least 600.

That along with a 40g fuge filled with assorted macros should be plenty of natural filtration , I hope.

 

[bertoni]

I haven't seen any indication that coralline algae affects the filtration capacity of live rock. I suppose it might, but I don't think anyone has any data on that.

 

[quiet reef]

After adding. 50 lbs rock 1 week later nitrates 20 ppm, nitries 4ppm. Waiting to see how parameters change. Adding my old skimmer to curing tank today

 

[Aquarist007]

Captain, do your experinces include curing some of the existing rock pieces to enhance their hospitality to bacteria? (or, swap an existing rock with a similarly sized LR or DR)

May be the actual question here is, how long it takes for a rock piece (and its bacterial flora) to start processing nitrites and nitrates (latter by anaerobics) ?

Aerobic bacteria can inhabit base rock within 3 to 5 days. Anaerobic bacteria take considerably longer
There are three necessary products for bacteria to grow: phosphates nitrates and carbon . If you have theses three then the bacteria will grow despite the surface you have provided.
Live rock can be problematic for bacterial growth when it becomes covered with detritus ect. Blasting it once a week with a power head will take care of that