Nitrate help

[Mal]

I am new at this. I have a 125 gallon tank setup for about 5-6 weeks. THe nitrates are at 20ppm and I can't get them down. I have been doing water changes, but it does not help.

We transfered 8 fish and 70lb of live rock from my son's 45 gallon. We have a sump with biobricks in it for reduction of nitrates. THe bio bricks are from the 45.

I want to set up a reef. how do you get the nitrates down?

 

[danmhippo]

A couple large water change will. What are you using for filtration? Skimmer? Are you using RODI? Are you feeding your tank heavily? Do you have DSB setup?

5-6 weeks is too early to tell if you are going to have steady high nitrate.

 

[wade1]

It sounds like you may be using a great deal of high oxygenation filtration (ie- bioballs, filter floss, wet/dry) and feeding a great deal. That type of filtration allows for the conversion of ammonia->nitrite->nitrate, but stops there. If you have the above mentioned LR and deep sand bed, then you get nitrate to nitrogen gas conversion.

Wade

 

[Mal]

My filtration is through the sump. The water comes down from the tank through drawers, into the sump. The top drawer is a filter pad, the next two have biobricks and Nitrex. The sump has a large protein skimmer. There is a second protein skimmer hanging on the tank. They are not prducing much waste.

I do not feed much. Some flake food twice a day. It is gone in 20 seconds.

I use all Reverse Osmosis water with 0 nitrates.

Io don't know what DSB is.

I have a 3" sand bed.

I was considering taking the biobricks out. Is that a good idea?


Thanks for the help

 

[jamesw]

Hi there,

As long as you have some "natural filtration" in your reef aquarium such as live rock and a live sand bed (also called deep sand bed) you can remove those bio-bricks. You might want to remove 1/2 of them, then the next week remove the remaining 1/2.

If you don't know about DSB and live sand, you MUST do a search on these forums and also visit the library at www.reefs.org/library Look up articles on "Live Sand" and "Deep Sand Bed."

Good luck!

James Wiseman

 

[Mal]

I did not know that DSB stand for deep sand bed. thank you.

I will try your suggestion. If I do, what result should I expect to see? Lower nitrates? Will amonia begin to rise?

My nitrates are now at about 20ppm. I was told that the ocean has nitrates of 30-40 ppm. Is this true?

What must my nitrates be to start to add corals, crabs, etc.?
I was told they must be Zero.

 

[danmhippo]

Normally, NO3 around 10ppm are acceptable, some species of coral can tolerate higher nitrate, some can't. Tanks with mature DSB can achieve 0 nitrate easily. With DSB incorporated, denitrifying bacteria deep within the sand bed breaks down Nitrate a step further. When the O2 in NO3 is being used up by denitrifying bacteria, the remaining NO does not get converted back to Nitrite or ammonia, so there should be no concern with rising ammonia level.

 

[Mal]

I have about 3-4" of crushed coral in my tank. Does that qualify as a deep sand bed?

 

[danmhippo]

No, one of the key qualification for DSB to work properly is sugar fine sand of at least 3-5" of sand bed. CC are too coarse and denitrifying zone will never develope due to too large a space between each "grain". Denitrification will only take place where O2 is scarce (or so called anaerobic zones).

 

[Mal]

I do have some fine sand in the tank, about 30 lbs, and about 120 lbs of aragonite.

If this is the wrong stuff, what should I have? I was told that this was the best to have.

 

[SPC]

Mal, you need "sugar fine sand" as Danmhippo said above.
Steve

 

[Anonymous]

look for stuff called 'oolitic' at your lfs(you can 'seed' it with small amounts of purchased live sand, or wait for it to seed itself via your rock, etc.(patience!).rinse it well, it's VERY dusty stuff.luck

 

[Mal]

Since I have CC as a base, can I add the sugar fine sand on top of the CC. Will that give the same result. Will the sugar fine sand go down into the CC and fill in the gaps to give the same result?

If I have 3" of CC as a base, how much fine sand should I add?

If this will work, will the existing CC act as live sand to seed the new sugar fine sand?

Mal

 

[Anonymous]

don't rinse it well, btw-my previous post was a mistake-i have learned abit more about oolitic on the bb...

recommended to not use the cc as a 'base'.however, the fine sand is dusty, and will cloud the tank-try siphoning out 1/5 of your cc bed at a time-and replacing that area with the fine sand.wait maybe a week between each swap.(if you soak the fine sand for a day or two previous to adding it to your tank, and add it through a tube-cloudiness will be minimalized)by the time you do each successive area, some of the critters will have migrated to the sand from the cc.
however, there's a good chance that your cc is lacking in a good number of the type of critters you want in your new sb(the larger grain is not the right habitat for 'em) so you may want to seed it again, with a true live sand package.
others, i'm sure, will chime in and let you know where you can get it,if not from your lfs, or add other options..

hth

 

[AF Founder]

I am new at this. I have a 125 gallon tank setup for about 5-6 weeks. THe nitrates are at 20ppm and I can't get them down. I have been doing water changes, but it does not help.

We transfered 8 fish and 70lb of live rock from my son's 45 gallon. We have a sump with biobricks in it for reduction of nitrates. THe bio bricks are from the 45.

I want to set up a reef. how do you get the nitrates down?

The advice that you have been given to reduce NO3 is solid. I would only add that if you have small particules in your water column you can remove them with a fine particle filter like a diatom filter.
Also, when it comes to reef tanks orthophosphate is far more critical. It has to be kept below 0.1 mg/L.
The struggle with reef tanks is to maintain a balance between the produces of waste and the consumers. The fish and feeding are the main producers and the corals, clams, algae, skimmers, and deep sand beds the consumers. This a little simplistic, but it gives you some sense of what's going on.

 

[Mal]

I have aquired southdown tropical play sand for my DSB. I am getting ready to replace the CC in my tank a section at a time as recommended.

My question is how to go about this. I will siphon it out. Should I take all of the CC coral out in that section or leave some of it and mix it into the fine sand. My CC has to have life in it! It has been in the tank for 6 months.

Mal



Advice given:

It is recommended to not use the cc as a 'base'.however, the fine sand is dusty, and will cloud the tank-try siphoning out 1/5 of your cc bed at a time-and replacing that area with the fine sand.wait maybe a week between each swap.(if you soak the fine sand for a day or two previous to adding it to your tank, and add it through a tube-cloudiness will be minimalized)by the time you do each successive area, some of the critters will have migrated to the sand from the cc.