Weird Nitrate problem

raf

Member
So I just bought a 95G Wavefront with a 30G sump, 150lbs of LR and 100lbs LS. The tank has been running for 3+ years and I brought all the water home with me (about 80%). The thing with this tank is that the sump broke a few months ago so it has been running with the protein skimmer only (Prizm). I got the tank home and set it up with a new sump and let it run for a few days but my levels are:
ammonia: .25
nitrite: 0
nitrate: 200+ (test kit only reads 200)
PH: 8.2
Anyone know what might have caused the high nitrates? The tank has had no livestock in it for a few months. I was thinking about getting some macro algae to see if it helps along with some water changes. I'm also wondering if it might cyce again but I doubt it because it still had LR, LS and flow this whole time.
THanks!
 

spanko

Active Member
Did you use the sand that was in the tank before the move? Could be a result of stirring up the sand releasing a lot of detritus.
Are you sure of the result of the testing, maybe you have an old test reagent for the nitrates? Have the LFS or another reefer verify the reading.
Do a large water change, 50% and see if it goes down.
 

raf

Member
Yeah I basically brought the whole tank home the way it was set up with all of the LR, LS and water. I have only changed out about 20% of the water and the new water had 0 nitrates. (or unmeasureable)
 

beaslbob

Well-Known Member
Sure you stirred everything up and now have high nitrates. Hopefully the tank itself will respond and things settle down.
To me what is important is to increase the nitrates consumers instead of relying on water changes. So the macro (and other) algaes are the way to go. Plus they balance out and stabilize the system also.
my .02
 

raf

Member
thats what I was thinking too. I still have to do a few water changes because when i got the tank the SG was 1.016 so I'm bringing it back up little by little. Any idea on what/how much macro to get? I heard about cheato and some other type but don't know what is recommended.
 

beaslbob

Well-Known Member
Originally Posted by raf
http:///forum/post/3224963
thats what I was thinking too. I still have to do a few water changes because when i got the tank the SG was 1.016 so I'm bringing it back up little by little. Any idea on what/how much macro to get? I heard about cheato and some other type but don't know what is recommended.
The various caulerpa are good nitrate (and phosphate) consumers but there are some reports of adverse effects to delicate corals like sps types. And in extreme cases they can sporate or go sexual as part of their reproduction systle. That careats a real mess. IME c. Profilera does best with NO type lighting but Grape (C. racemosa?) requires higher lighting.
Chaeto is good also and just grows to whatver size and shape the container is. Plus pods, snails, and other critters thrive in it.
Both do best protected from fish and cleaner crews in some kind of refugium.
You can bring up salinity be adding small amounts of salt also instead of the water changes.
Nitrates can peg a test kit for months. Then all the sudden (like is a day or two) drop down to unmesureable levels. You also may notice an increase in the just before lights out pH values also as the macro consumes carbon dioxide.
Some macro algaes like halimeda are "hard" (calcius) and actually require reef like conditions. They tend to be slower growing but more immune to fish and cleaner crew effects.
my .02
 

raf

Member
how long does it usually take for the nitrates to lower using macro? I put in about 2 generous double-handfulls.
Would doing a 50% water change send the tank through a cycle?
 

beaslbob

Well-Known Member
Originally Posted by raf
http:///forum/post/3226179
how long does it usually take for the nitrates to lower using macro? I put in about 2 generous double-handfulls.
Would doing a 50% water change send the tank through a cycle?
It can take several months as the plant life expands. But then at some point all the sudden nitrates will drop to 0 in a day or two. Especially with nitrates that are pegging your test kit. Because you cannot measure movement above that level. For instance, if nitrates dropped from 600ppm to 300ppm the test kit would not reflect that.
Actually your parameters do look good. PH is up and ammonia of .25ppm can just be a measurement error. I use the api test kit and always measure .25 ppm because the color changes at that level are hard to read.
It is very possible a 50% water change would kick off a cycle. But even with that the macros actually prefer to consume ammonia over nitrates. So what happens the extra ammonia can (will) be rapidily consumed by the macros preventing dangerous ammonia spikes.
my .02
 

bulldog123

Member
Is there any live stock in the tank? I would of change 80-90% of the water in the first place. What would be the benefit of using old water? Other than saving on salt money!
 

beaslbob

Well-Known Member
Originally Posted by spanko
http:///forum/post/3226297
How does - would a 50% water change kick off an ammonia spike?
By stirring things up, possibily adding toxins, changing all parameters and so on.
If you have an otherwise healthy tank but are measureing nitrates ( high or otherwise), IMHO it is much safer to increase the nitrates consumers then do water changes.
for instance as anaerobic bacteria or plant life (macros) consume the nitrates, both processes return carbonates used up by the aerobic bacteria that reduced the ammonia and nitrItes to nitrates.
my .02
 

raf

Member
OK I did 50 gallons today and the nitrates dropped to 160. If I do another 50 tomorrow, will it decrease by 50% (roughly)?
What is a safe nitrate level for fish? I heard some FOWLR tanks have 80ppm nitrates without any effects and I know some books written by experts state that its not scientifically proven that nitrates are harmful to fish. Any input?
 

spanko

Active Member
Yes, higher nitrates are acceptable in a fish only tank with regards to the fish. However the caveat here is that higher nitrate levels, as our friend beaslbob has pointed out, will fuel algae growth. In order to keep any of the unwanted algae at bay you will need to outcompete it with other macro's or reduce the nitrates in some other way.
 

raf

Member
yeah I'm not thinking about leaving the nitrates there long-term. My QT is a little overcrowded so I wanted to start putting a fish or two in DT. Eventually I'll try to get the nitrates back down to at least under 40. Will it be OK then?
 
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