Nitrate mystery....is it the sand?

[mjs]

Established tank...3 years
80 gallons + 10 gallon sump
80 lbs live rock
Large protein skimmer
salt 1.023
ph 8.25- 8.35 steady
Ammonia- trace
Calcium 375
phos- 0
kh-8
NITRATE 60- 80

About 8 months ago I converted from crushed coral bottom to sand.
I do a 10- 15 gallon water change every week with r/o, tested to 0 nitrate.
There are no recent fish deaths or snail die offs.
But, the nitrate just will not come down.

I have done a major change (25 gallons)twice in the last two months.
Climbed back up

Is it possible that the sand is the problem??
I used to use the vacuum in the coral and "clean" it up periodically.
Obviously cant do that with the sand.
Is there a protocal for sand bottom tanks that I am not following....

Or..any other ideas???

 

[Krish]

Hmm...I was thinking it could possibly be the rocks. They may be clogged and need to be "cooked" as they say, but not sure...About the sand, was it new sand you used or was it from another tank?

 

[mmkeeper]

Are you feeding the tank to much?

 

[jsmkmavity]

are you using mechanical filtration of some kind? if so are you leaving the filters in for more than a few days without cleaning or changing them? do you have bio-balls?

 

[mjs]

feeding has been as usual, even a bit lighter since the nitrate rise.
the sand was new, but its been 8 months now
no mechanical filtration being used and no bio balls

whats this rock "cooking" ???

 

[Krish]

Basically what I understand about the whole concept is that if your rock becomes so saturated or "full" and cannot perform it's bio-logical functions anymore, then people usually "cook" it as they call it, (not physically in a pot of noiling water) but by putting it in a dark place with high flow until the rock can "function" bio-logically again (mainly denitrification) I've never personally done but there is talk about it all the time on the forum. I just mentioned it because I've heard people having to do it when it seems the LR could no-longer denitrify. I'm honestly no expert on the subject but this thread may help you a bit. I think they spoke of it a bit here...

http://www.reeffrontiers.com/forums/showthread.php?t=11905&highlight=cooking+lr

 

[mojoreef]

What kind of salt are you using, and have you checked your test kit?? is it out of date


Mike

 

[tike]

Another question is.......How deep is your sand bed???
I fought high nitrates in a tank with a 3" sand bed for months. The tank was set up for 3 years with no problems and then.......nitrates thru the window. I tried weekly water changes....adding a refugium....switching salt mixes...nothing worked until i totally removed the sand bed and ran BB. I haven't had a problem since. So my advice is either, add on a refugium of 30-40 gallons and see if that works or removing the sand bed.

 

[Paul B]

I don't really believe in that rock saturation thing, especially in a three year old reef. My rocks are in there over 30 years and my nitrates are zero.
I also believe crushed coral would be better at lowering nitrates since it is porous and sand is not but I doubt that would make that much difference.
The reading does sound high. I agree with Mike, borrow someone else's test kit or bring some water to a LFS that will test it for you.
Paul

 

[mjs]

thanks everyone....
going to try and remove the sand bed over the next few weeks, a little at a time

 

[Krish]

I don't really believe in that rock saturation thing, especially in a three year old reef.

Why not Paul? I hear talk about it all the time on the board about people having to cook their rock? Infact Nikki had to if I remember correctly. I've never done it or had to, but I'm sure it does happen if people are having a rock saturation issue. Also, if infact it does happen, you can't say that can't be the case in a 3 year old system when the rock may be much older than that coming from another system and also from not knowing the condition of the rock in this particular tank...Just a thought. Like I've said, don't really know much about the subject, just hear it time to time here

I also believe crushed coral would be better at lowering nitrates since it is porous and sand is not but I doubt that would make that much difference

I always thought crushed corals were bad because they were not able to perform denitrification whereas a dsb using sand can perform denitrification in it's lower anaerobic region or am I mis-understanding what you meant?

 

[Scooterman]

Paul, I think in some cases these rocks that became saturated because of several reasons , I'm sure they were still working fine but also had so much food to feed unwanted alga's it becomes a problem, maybe they had the rocks jammed up where stuff collected on it for some time & it was producing algae so much it was a problems to keep, I'm sure if it was just one rock & you stayed on it you could clear it up but for several reasons it doesn't always happen. You can read that thread if interested it can give someone thought as to what was happing. As far as the sand cc think, sand of varying sizes will outperform the cc in many ways, you can read up on that plenty here or from Dr. Ron, if you wish. In no way am I knocking your experience in keeping a reef 30 years just maybe some people hasn't gone through what you did or do for that matter. On the subject it could be that he was able to remove the waste & never had problems. maybe needs retesting like mentioned, may be the sand hasn't established throughly yet & is causing some cycling, or maybe the rocks are under higher demands because he removed everything from the cc before it became a problem & now he can't vacuum thus the rocks are working harder, the sand isn't ready to make up if difference. Just for food for thought.

 

[Paul B]

Krish as to the sand, it doesen't say if it is a DSB. If it were a DSB I would feel different, if it's just a fine layer of sand then I would think CC would be better as it is porous and basically just small pieces of live rock. My substrait is dolomite which is similar to CC. Although, either way I don't think it would make much difference.
Scooty, I know about Dr. Ron, he got into the hobby the same year as me, I know his views and I am in no way more knowledeable than him, but he does not have an old tank himself (as far as I know)
I realize there are many people who "cook" rocks and seem to have good results. I have a problem with it but I don't nessisarilly doubt that it could work. My problem with it (and it's only my opinion from 40 years of dealing with it) is that first of all these rocks that we are calling one or two years old were in the sea for hundreds of years before we collected them (OK they do not get as dirty in the sea, I agree to that) and the rock in my reef is almost 40 years old. Thats all I could go by. Why would rocks get saturated in three years if mine are fine after 40. I overfeed and do all sorts of experiments.
I do powerwash the rock every once in a while with a diatom filter but I doubt that makes much difference, after all I can't reach the back or bottom.
Does everyone remove their rocks in three years because of saturation? Do public aquariums do it? I don't think so.
Many of us (including myself) occasionally get algae problems, I don't take this as a problem or always being caused by bad husbandry, Algae is a natural part of any healthy reef. I have dove in just about all the oceans and the urchins, snails, tangs and slugs are there because there is algae there. They eat it as soon as it grows so you don't see it and the ocean has enough volume to process the wastes of these animals and most of the ocean is too deep for algae to grow. Of course we don't want to see it in our reefs and especially not on our corals so we resort to using DSBs, live rock water changes de-nitrofiers etc.
Back to saturation of rock, I am not saying it can't happen, I don't know. I am saying that in my experience, with an old tank, it did not happen to me.
I also think when we get an algae cycle, which most older tanks get, it clears up on it's own and we may think that cooking the rock worked.
Now don't jump all over me about my views on algae, I know many people will disagree with me and thats fine. My opinions are based on experience and many years of diving. I go diving basically to learn and not just to look at the pretty fish :lol: I look closely between and under the rocks to see what is growing and whats eating it.
Have a great day.
Paul

 

[Scooterman]

No Paul I can't disagree with you on that, what your saying seems very logical & I understand where your coming from, one thing I didn't mention & this may belong in that thread but people don't want to wait it out sometimes it takes a while to cycle the algae out this may be because when using DSB's you don't get that until you have sudden problems with the DSB. When I had cyno all I did was harvest it & eventually it went away. In my case I had an invasion of razor & that long skinny algae, It was spreading all over & not going away. I could deal with the regular algae the green stuff on the rocks. but the combination of the two got bad. I inherited the razor & that other type before I put whatever rocks that carried it I have no issues with it so maybe you never had to deal with those problems, also BB tanks rely more on LR so that adds to the equation. I also think cc if you vacuum it then you remove the most of problem quickly, although you may not be able to remove it all in spots, going to a sb that would change things.

 

[Paul B]

Scooty, I know, I also have some problems but I think mine are due to the fact that I add all sorts of things from northern (not tropical) water like seaweed, rock, amphipods etc. Sometimes one of these algaes take hold and cause me some concern for a while until it disappears which it always has.
Sometimes I get an algae cycle which lasts a few months, most people would go crazy but I know the algae will exhaust whatever it needs to grow and when that happens it dies very fast. Now I have an algae trough above the tank where the algae can happily grow in my water but stay out of my tank.
This year was probably the first year where the algae cycle all grew in the trough and none of it comes into the tank. I actually think this is the solution to all these algae problems, let it grow, just force it to grow outside of your tank. I always laugh when I read how people solved their algae problem by snails, crabs seahares, slugs whatever when in all probability the algae completed it's cycle and left. A couple of crabs will not eat an entire tank of algae but people still think thats what happened.:badgrin:
Have a great day.
Paul

 

[Skimmy]

i for one am a large fan of rock cooking and i have personally seen the positive results of "cooking" my rock and the rock of countless other peoples tanks over and over again, so i know it works.
it's not a magic bullet that will rid your tank of all trate or phos either, so i guess it's success is dependant upon what you are doing it for.
i do it because in tanks with improper amounts of flow, sandbeds improperly maintained, or just all around poor maintenance habits, it's not uncommon for the rocks to become saturated with detritus to the point that the porosity is severly affected.
by taking the rock out of the photosynthetic environment, and putting it in a high flow evironment preferably with a skimmer and then doing water changes every several days and violently shaking the rocks during those water changes you can get the rock back to the point of being clean, algae free, and porous again. so from that standpoint, for me rock cooking has been very helpful.

 

[Krish]

Thanks for the feedback Paul...I had a terrible algae problem when first getting into the hobby about 2 years ago and couldn't get rid of it. My problem came from using well water that had over 160ppm of nitrates in it. 2 seperate 100% water changes made no difference for me especially seeing I took out the rocks and scrubbed them in the same well water. So my way of dealing with it was take out all of the rocks, gave some away and the rest, I tossed in the yard under the sun and let them sit for about 6 months. What that left me with was base rock which is now in my tank along with some new LR I purchased to seed the tank. My tank has been up and running going on 10 months now and doing great. I figured trying to "wait it out" with the nitrate filled rocks wouldn't work for me so I "killed it". In any event, I personally feel a rock can become saturated from my own personal experience. I feel that in some cases, the limited supply of rock we have in our tanks can only perform so much denitrification, and sometimes it's just not enough to battle some of the problems sometimes on its own unless you've got nothing but time on your hands to wait. I think what helps people not have this problem with their rocks becomming "saturated" is by having help by other means of dealing with the problem like refugiums, algae troughs, dsb, skimmers, good husbandry etc which doesn't leave all of the work up to the LR itself...Like I've said, no expert on the subject, just my point of view

 

[Paul B]

Krish, I agree good husbandry, skimmers, algae filters, whatever will all help, they are all tools without which we could not be in this hobby. I was in this hobby before we had any of those things including live rock. We had to remove the rocks every few weeks to soak in bleach. Thats the way all salt tanks were in the early seventees. We knew nothing about nitrates, there were no kits, my nitrates were probably over 100. I also had triggers, morays, puffers, lionfish and any other meat eating type of fish that looked cool. We didn't care how many goldfish we threw in there either.
Now it's a little different and we gained some knowlege.
Weather you want to cook your rock or not is what makes this hobby interesting. It won't hurt and if you think it helps then by all means do it.
If you think snails will eat all your algae, put in snails. No one here is wrong and there is not just one thing that will work in all tanks. These tiny ecosystems are vastly more complicated on a macro level that many people realize and doing one thing in one tank may have disasaterous results in another tank.
Have a great day.
Paul

 

[Krish]

Krish, I agree good husbandry, skimmers, algae filters, whatever will all help, they are all tools without which we could not be in this hobby. I was in this hobby before we had any of those things including live rock. We had to remove the rocks every few weeks to soak in bleach. Thats the way all salt tanks were in the early seventees. We knew nothing about nitrates, there were no kits, my nitrates were probably over 100. I also had triggers, morays, puffers, lionfish and any other meat eating type of fish that looked cool. We didn't care how many goldfish we threw in there either.
Now it's a little different and we gained some knowlege.
Weather you want to cook your rock or not is what makes this hobby interesting. It won't hurt and if you think it helps then by all means do it.
If you think snails will eat all your algae, put in snails. No one here is wrong and there is not just one thing that will work in all tanks. These tiny ecosystems are vastly more complicated on a macro level that many people realize and doing one thing in one tank may have disasaterous results in another tank.
Have a great day.
Paul

Just goes to show the diversity of the hobby...Makes things so much more interesting. Thanks again for your words of wisdom and experience

 

[Scooterman]

We didn't care how many goldfish we threw in there either.
Paul

LMAO!!!!!!:lol: :lol: :lol:
poor little fishes!