Are elevated nitrates normal for tank less than a year old?

[Newguy33190]

46 bowfront, 65lbs of dry rock from reef cleaners, 40 lbs sand, 2 koralia evo 750s, dual cartridge hob filter with carbon filter pads. 2 clowns, 1 pj Cardinal, 1 damsel

 

Tank cycled 10 days ago after having really high ammonia and nitrites. Qt tank gave me problems so I was forced to put the fish in the dt. No levels spiked so all was good. I was able to get my nitrates down to 0 for 2 days last week and since then they seem to be at 20ppm. I do a 8 gallon water change, clean the filter cartridges and they stay at 20ppm. I feed once a day only what is consumed in a couple minutes, use rodi water that the levels are good. I blew all the rocks off and only changed the 8 gallons of water so it could be possible A lot of crap was left in the tank. I believe I'm just starting to get diatoms so I'm sure the uglies are coming.

 

If it is normal to have nitrates in a tank under a year old then I won't worry about it but if an issue I want to address it right away.

[BuddhaReef]

Don't want to be that guy... but the best bet is your tank wasn't fully cycled or at least was on the last stage when you introduced the fish and reset the nitrate conversion. I'd continue doing water changes with higher frequency and if you like black magic, possibly try a product like MB-7 or bacter gen-m to seed more nitrifying bacteria.

[Newguy33190]

Don't want to be that guy... but the best bet is your tank wasn't fully cycled or at least was on the last stage when you introduced the fish and reset the nitrate conversion. I'd continue doing water changes with higher frequency and if you like black magic, possibly try a product like MB-7 or bacter gen-m to seed more denitrifying bacteria.

if I reset it wouldn't the tank have an ammonia spike? Not that I'm against additives but even with fish in the tank won't my denitrifying bacteria grow?

[Newguy33190]

If the bacteria that convert waste to ammonia and ammonia to nitrites were already settled in so to speak, introducing fish would indeed allow more ammonia and nitrite into the system. but supposing they had substantial numbers to process the new bio-load, possibly only the nitrobacter had not yet established sufficiently to handle the elevated levels of nitrites, causing a nitrobacter bloom. As a result, elevated levels of nitrates.

Should I just continue my weekly maintenance and check in a few weeks to see if it stabilizes?

[BuddhaReef]

Yes the populations will increase but more than likely at a slower rate and possibly exposing livestock to less than ideal water conditions.

 

I personally am a fan of SeaChem prime, which can help 'detoxify' ammonia and trites and trates and reduce fish stress. The additives I mentioned are supposedly designed specifically with marine environments in mind, adding to the biodiversity and numbers of your biofilter, allowing for a 'quicker' cycle completion.

 

 

Nitrates are semi-natural (in the sense it signifies an active biofilter) though, it isn't the biggest issue, but one that can certainly be addressed now.

[jestep]

Nitrates are normal starting any time a tank has water in it and has some amount of nitrifying bacteria which you established during the cycle. As soon as you put a nutrient source in the tank, you're going to end up with nitrates.

 

As far as denitrifying bacteria, you're not going to have any for months, and most likely in this size tank, denitrifying bacteria are probably going to be insignificant unless you are using something like biopellets or another carbon source. Assume the tank isn't going to process nitrate on its own.

 

I would get on a routine water change schedule like 10% per week and feed every other day see how your levels react over the course of the next 2 - 3 months. Right now, and for the first 6 months to a year, the tank will go through a ton of changes, best not to take drastic action unless there is good reason to. Also, if you're using API NO3 test kits, I'd get something else. These and their PO4 tests are so inaccurate they're worse than just eyeballing the tank in my experience.

[BuddhaReef]

Should I just continue my weekly maintenance and check in a few weeks to see if it stabilizes?

A little more water out and feed a little less, but yeah.

[Newguy33190]

Nitrates are normal starting any time a tank has water in it and has some amount of nitrifying bacteria which you established during the cycle. As soon as you put a nutrient source in the tank, you're going to end up with nitrates.

 

As far as denitrifying bacteria, you're not going to have any for months, and most likely in this size tank, denitrifying bacteria are probably going to be insignificant unless you are using something like biopellets or another carbon source. Assume the tank isn't going to process nitrate on its own.

 

I would get on a routine water change schedule like 10% per week and feed every other day see how your levels react over the course of the next 2 - 3 months. Right now, and for the first 6 months to a year, the tank will go through a ton of changes, best not to take drastic action unless there is good reason to. Also, if you're using API NO3 test kits, I'd get something else. These and their PO4 tests are so inaccurate they're worse than just eyeballing the tank in my experience.

I'll look into another test kit and cut back on feeding. Iv had the same cartridges in my filter since day one and just rinse them off. Should I toss them, clean the filter, do a little water change and run the filter empty to see if it's the cartridges adding to the nitrates?

[chipmunkofdoom2]

It's also important to understand the math of water changes. Assuming the new saltwater you put in the tank has no nitrates, the reduction in nitrate levels will be equal to the overall reduction in water volume.

 

Your tank is 46 gallons. Let's assume it contains about 40 gallons of water since your rock and sand displace some of the 46g overall volume. The actual math might vary based on how much water you truly have in the tank, but 40g is a good enough ballpark guess. When you change 8 gallons of water out of 40 gallons of total tank volume, you're changing 20% of the tank's water (8 gallons / 40 gallons = .2, or 20% water change). When you replace water with 20ppm of nitrates with nitrate-free water, the reduction is equal to the amount of water removed. In this case you removed 20% of the water, so 20% of 20ppm is a 4ppm reduction. So in this case, your water change reduced your nitrates by 4 ppm to 16ppm. A reduction, but not a very large one. If there are left over nitrates from decaying matter on the rock or if you're over-feeding, this much of a reduction isn't going to make a huge difference. To illustrate my point, if you wanted to cut your nitrates in half, you'd have to change half of your water, or 20 gallons.

 

Sorry, this is somewhat of a complex answer and may have been more information than you wanted. It's useful to keep in mind, however, when trying to come up with a long-term nitrate remediation strategy.

 

A little more on topic, if your rock had a lot of die-off, that means a lot of ammonia was/is still being produced, which eventually gets turned into nitrates. You may have high nitrates for a while if this is the case. Just try to watch the feeding and keep up with the water changes.

[brandon429]

expect no denitrification for the life of your tank, it was overblown

 

that's why people use biopellets, vodka, ats, denitrators, all to get to the real nitrate control. in tank stuff was fully overblown, or those items wouldn't exist or be needed

 

berlin method was the hype train

 

not that it was bad, just that live rock and ls doesn't degas in 99.99% of tanks so yours is in no problem condition. no reset needed. your waste sinking in the sandbed is the likely cause, detritus retention mostly. no other cause, no bac imbalances.

[jestep]

I'll look into another test kit and cut back on feeding. Iv had the same cartridges in my filter since day one and just rinse them off. Should I toss them, clean the filter, do a little water change and run the filter empty to see if it's the cartridges adding to the nitrates?

 

Are they both carbon pads? You might try switching to plain filter floss or poly and just change them out once or twice a week.

[Newguy33190]

I get what your saying. The rock was dry rock from reef cleaners that I rinsed really well so their shouldn't be any die off. I would like to make it so I don't need a 40 gallon water change every week to get my nitrates under 5ppm, that possible?

 

Are they both carbon pads? You might try switching to plain filter floss or poly and just change them out once or twice a week.

Yes both carbon and since they were in there from the cycle I want to change them reguardless. I'll toss them and get regular pads.

expect no denitrification for the life of your tank, it was overblown

 

that's why people use biopellets, vodka, ats, denitrators, all to get to the real nitrate control. in tank stuff was fully overblown, or those items wouldn't exist or be needed

 

berlin method was the hype train

 

not that it was bad, just that live rock and ls doesn't degas in 99.99% of tanks so yours is in no problem condition. no reset needed. your waste sinking in the sandbed is the likely cause, detritus retention mostly. no other cause, no bac imbalances.

You think since Iv only had fish in for 10 days that there's enough crap built up on the sand (if so I can't see it) that it would cause nitrates to elevate quickly? I'll vacuum close to the sand bed enough to suck up whatever is there and see if that's the cause

[brandon429]

oh sure if its that new its fine but id test for sure.

if cloud, rinse and nitrate time

 

even live rock contributes, produces, not reduces, detritus. there are some stores in the sand but if only ten days worth that may not be the major source, id move to fish excretion after that in the hunt.

[BuddhaReef]

Sorry for the mispoken 'denitrifying' earlier, I think I confused the OP. Just like guys to be wanting to put the 'de' on everything.

[brandon429]

its also unfair to denitrification formal studies one can google scholar if we don't talk about where it does happen

 

 

in massive dilution settings it plays a measurable role in movement of N

 

in our nanos packed w fish, even large tanks, not so much. its trace levels.

 

occurring in biofilms, live rock we kept porous by not letting it get plugged with detritus, in deep and shallow sandbeds, true N2 degassing happens constantly

 

just not to any degree that offsets our savage needs for bioload per gallon heh

 

sure there are people out there with ideal live rock. ideal bioloads, true degassers. can't discount stat outliers. outliers they shall remain, the rest have tanks on the 12 step program for feeding them our liquor cabinets (old school VSV joke heh)

[Newguy33190]

I'm getting little spots of brown diatoms here and there on the rocks so hopefully the algae stage comes and goes and the nitrates become more stable