What can i do/clean to lower very high nitrates?

Reef_at_Sea

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Hello,

I am still struggling with insane high nitrates & i still don’t know the reason why.

I don’t feed alot. I have 8 small-medium sized fish in a 50g tank (2x clown, 1x links goby, 1x midas blenny, 1x lawnmower blenny, 1x pink streaked wrasse, 1x fridmani basslet, 1x dwarf flame angel) & a clean up crew of about 8 snails & 3 hermit crabs.

My skimmer takes about 2 days to fill a cup & i am dosing nopox & tried vodka/vinegar for a while now but nothing helps except huge water changes. But nitrates creep up after that again.

Are there any steps that i can test or i should do before i make the decision to remove fish?
Should i vacuum my sand thoroughly or something? I removed my filter socks because i hated them & changed to floss in filter cups. I change the floss every day.

Note that my tank had high nitrates even before i added fish so i’m starting to think something is wrong with my bacteria household.

I have about 20kg of rock & 2liters of biospheres in my AIO sump.

Please help me because idk what to do anymore.. :(

I’m talking about 75ppm or higher
phosphate usually drops down to 0,02 in about 1-2 days so i dose phosphate to help remove nitrate.

I will answer every question honestly so you can help me the best

8DD39458-4E6B-4FED-BA96-8626657B5E4F.jpeg
 

sixty_reefer

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I believe you may have answered your question, there is a possibility that your phosphate is lower than you think it is.
Personally I would keep it above 0.05 to eradicate test error
 

ReeferDog

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If you want to vacuum your sand bed, I would not do it all in one shot. Do it in smaller sections like 20% or 25% of the sand bed across multiple water changes. Disturbing the entire sand bed at once could cause a nutrient spike.
Inspect the bottom of your AIO sump for detritus build up and vac that out if there is any. As long as you rinse your AIO bio media in tank water (can be 'outgoing' water from a recent water change), you can flush any detritus from the rock and bio-spheres in there.
For good measure, I'd also take a powerhead or turkey baster and blow off your entire rock structure right before your next water change to get any detritus suspended in the water column for you to remove or your filter to pull it out.
You could also dial back your skimmer to get more of a dry skim compared to a wet skim, if you're not doing that already.
Since you are in the EU.... have you ever had your source water tested for Nitrates? If you're getting it from a LFS, then you're probably fine.

Good Luck.
 
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Reef_at_Sea

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If you want to vacuum your sand bed, I would not do it all in one shot. Do it in smaller sections like 20% or 25% of the sand bed across multiple water changes. Disturbing the entire sand bed at once could cause a nutrient spike.
Inspect the bottom of your AIO sump for detritus build up and vac that out if there is any. As long as you rinse your AIO bio media in tank water (can be 'outgoing' water from a recent water change), you can flush any detritus from the rock and bio-spheres in there.
For good measure, I'd also take a powerhead or turkey baster and blow off your entire rock structure right before your next water change to get any detritus suspended in the water column for you to remove or your filter to pull it out.
You could also dial back your skimmer to get more of a dry skim compared to a wet skim, if you're not doing that already.
Since you are in the EU.... have you ever had your source water tested for Nitrates? If you're getting it from a LFS, then you're probably fine.

Good Luck.
Hmm, i've always read mixed comments about vacuuming a sand bed & i'm kinda scared of it because it might cause a nitrate spike.

I thought that you should always run wet skim instead of dry skim when dosing nopox or carbon source?
I did test my newly made salt water & it has undetectable nitrates.
 

TangerineSpeedo

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Put some easy SPS in your tank... that will suck all the nutrients out...
How often do you do water changes and at what percentage?
Also a filter roller will help. I do not know which AIO tank you have but there may be a commercial or private filter roller for your tank. The AIO tank I have always seems to have high nutrients. most ppl. have a hard time with Po4 export but with nitrates water changes will take care of them. You can do a 5g water change every day until they come down. And a side note double check with another test kit just to be sure.
 
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Put some easy SPS in your tank... that will suck all the nutrients out...
How often do you do water changes and at what percentage?
Also a filter roller will help. I do not know which AIO tank you have but there may be a commercial or private filter roller for your tank. The AIO tank I have always seems to have high nutrients. most ppl. have a hard time with Po4 export but with nitrates water changes will take care of them. You can do a 5g water change every day until they come down. And a side note double check with another test kit just to be sure.
Easy sps? won't those just die in nitrates 75ppm?
i do a 25% water change every 2 weeks.
I use filter floss in a media cup that i change every day, filter rollers are not available sadly...
I don't have any problems with po4 export, only problems with high nitrates.
i did double check with an ICP.

i am doing large water changes atm to get it down asap, i'm also thinking about using bio-pellets/blocks.
 

TangerineSpeedo

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Easy sps? won't those just die in nitrates 75ppm?
i do a 25% water change every 2 weeks.
I use filter floss in a media cup that i change every day, filter rollers are not available sadly...
I don't have any problems with po4 export, only problems with high nitrates.
i did double check with an ICP.

i am doing large water changes atm to get it down asap, i'm also thinking about using bio-pellets/blocks.
Bio pellets will pull both No3 and Po4 and you have low Po4 so that may create more havoc in your tank.
I would try a 10g water change every other day until your No3 is manageable. then put in some easy sps (porcillipora, green birdsnest, etc.) Anything that your fellow reefers locally can not get rid of fast enough.
It is hard to tell, but from your FTS it doesn’t seem like you have any algae issues.
 
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Bio pellets will pull both No3 and Po4 and you have low Po4 so that may create more havoc in your tank.
I would try a 10g water change every other day until your No3 is manageable. then put in some easy sps (porcillipora, green birdsnest, etc.) Anything that your fellow reefers locally can not get rid of fast enough.
It is hard to tell, but from your FTS it doesn’t seem like you have any algae issues.
I don’t have algea issues at all ha.
 

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So what is the problem besides a high reading for nitrate? If you don't see negative effects I wouldn't worry too much.
 

Dan_P

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Hello,

I am still struggling with insane high nitrates & i still don’t know the reason why.

I don’t feed alot. I have 8 small-medium sized fish in a 50g tank (2x clown, 1x links goby, 1x midas blenny, 1x lawnmower blenny, 1x pink streaked wrasse, 1x fridmani basslet, 1x dwarf flame angel) & a clean up crew of about 8 snails & 3 hermit crabs.

My skimmer takes about 2 days to fill a cup & i am dosing nopox & tried vodka/vinegar for a while now but nothing helps except huge water changes. But nitrates creep up after that again.

Are there any steps that i can test or i should do before i make the decision to remove fish?
Should i vacuum my sand thoroughly or something? I removed my filter socks because i hated them & changed to floss in filter cups. I change the floss every day.

Note that my tank had high nitrates even before i added fish so i’m starting to think something is wrong with my bacteria household.

I have about 20kg of rock & 2liters of biospheres in my AIO sump.

Please help me because idk what to do anymore.. :(

I’m talking about 75ppm or higher
phosphate usually drops down to 0,02 in about 1-2 days so i dose phosphate to help remove nitrate.

I will answer every question honestly so you can help me the best

8DD39458-4E6B-4FED-BA96-8626657B5E4F.jpeg

How old is the aquarium?

Have you confirmed that nitrite is not present?

What was the highest dose of vinegar or ethanol before you switched to NOPOX?
 

Dan_P

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Tank is 6-7 months old, no nitrite present.
Highest dose was 40ml vinegar.


If you started with high nitrate, you might need to do a large water change to bring it down to where you want it to be. Reducing nitrate with macro algae or vinegar dosing can take a month or two starting at 70 ppm. Controlling an increase in nitrate is much easier than trying to get rid of a large amount plus the new nitrate being generated every day.
 
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If you started with high nitrate, you might need to do a large water change to bring it down to where you want it to be. Reducing nitrate with macro algae or vinegar dosing can take a month or two starting at 70 ppm. Controlling an increase in nitrate is much easier than trying to get rid of a large amount plus the new nitrate being generated every day.
Yeah, i just started doing 30% water changes every 2 days or so, but now my RODI seems to have decreased in quality, so i'm stuck...

This afternoon i'm going to the LFS to get a TDS meter & some RODI water + they also seem to have bio blocks that can break down nitrates without phosphates, somoene i know uses them & tells me they work but they also take time to work.
 

Dan_P

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Yeah, i just started doing 30% water changes every 2 days or so, but now my RODI seems to have decreased in quality, so i'm stuck...

This afternoon i'm going to the LFS to get a TDS meter & some RODI water + they also seem to have bio blocks that can break down nitrates without phosphates, somoene i know uses them & tells me they work but they also take time to work.
Denitrification can take weeks to start working.

Good luck!
 

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This all sounds like there is something wrong in the basis.
I would suggest taking measures to increase the overall metabolism of the tank.
That means: increase lighting and flow.

I see four flow pumps. Make them work.
Your corals can take more than you think.

Run high intensity blue and white channels for 6 hours of your schedule.
If your two lights together are ~100W or less. Run them on 100%. You may want to add a third light in this case.

Doing this will make all photosynthetic organisms work harder and take up the nutrients in your tank.
Yes, this includes algae, but with enough herbivores your corals will win. The herbivores will turn those algae into their own mass, detritus for detritivores and skimmable waste.

By the sounds of it, your skimmer might be undersized or running sub-optimally.

Besides this, the sand cleaning advice I would give as well.
And to remove any biological filtration (bioballs, ceramic spheres/blocks etc).
Basically: minimize surfaces in dark oxygen rich areas where nitrification (nitraat making) can take place.

Easy sps? won't those just die in nitrates 75ppm?
i do a 25% water change every 2 weeks.
I use filter floss in a media cup that i change every day, filter rollers are not available sadly...
I don't have any problems with po4 export, only problems with high nitrates.
i did double check with an ICP.

i am doing large water changes atm to get it down asap, i'm also thinking about using bio-pellets/blocks.
Die?

My previous tank. NO3 at 70. Was over 90 a couple of months earlier. Nothing dead, all growing.
1736934954057.png


Four months later compared to the previous picture. NO3 still 40. Acros starting to touch the water's surface...
1736935133960.png
 
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This all sounds like there is something wrong in the basis.
I would suggest taking measures to increase the overall metabolism of the tank.
That means: increase lighting and flow.

I see four flow pumps. Make them work.
Your corals can take more than you think.

Run high intensity blue and white channels for 6 hours of your schedule.
If your two lights together are ~100W or less. Run them on 100%. You may want to add a third light in this case.

Doing this will make all photosynthetic organisms work harder and take up the nutrients in your tank.
Yes, this includes algae, but with enough herbivores your corals will win. The herbivores will turn those algae into their own mass, detritus for detritivores and skimmable waste.

By the sounds of it, your skimmer might be undersized or running sub-optimally.

Besides this, the sand cleaning advice I would give as well.
And to remove any biological filtration (bioballs, ceramic spheres/blocks etc).
Basically: minimize surfaces in dark areas oxygen rich areas where nitrification (nitraat making) can take place.


Die?

My previous tank. NO3 at 70. Was over 90 a couple of months earlier. Nothing dead, all growing.
1736934954057.png


Four months later compared to the previous picture. NO3 still 40. Acros starting to touch the water's surface...
1736935133960.png
Wait what?!!!

I had a montipora frag a while ago in the same nitrate conditions and all it did was just brown out & die...
My tank is a LPS & softies only tank so i don't run my lights full power, i have about 170 PAR where my torches are, the lights are 2x Ai Primes 16hd on the pennywise deadlights 81% schedule.

You are telling me to remove the ecotech biospheres in my AIO sump? aren't those benificial to increase nitrification surface? i will rinse them while water changing.

i am slowly increasing the flow lately, although flow is always a struggle...

I have a tunze doc 9004dc skimmer, wich should even be oversized for the tank instead of undersized..
 
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Reef_at_Sea

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This all sounds like there is something wrong in the basis.
I would suggest taking measures to increase the overall metabolism of the tank.
That means: increase lighting and flow.

I see four flow pumps. Make them work.
Your corals can take more than you think.

Run high intensity blue and white channels for 6 hours of your schedule.
If your two lights together are ~100W or less. Run them on 100%. You may want to add a third light in this case.

Doing this will make all photosynthetic organisms work harder and take up the nutrients in your tank.
Yes, this includes algae, but with enough herbivores your corals will win. The herbivores will turn those algae into their own mass, detritus for detritivores and skimmable waste.

By the sounds of it, your skimmer might be undersized or running sub-optimally.

Besides this, the sand cleaning advice I would give as well.
And to remove any biological filtration (bioballs, ceramic spheres/blocks etc).
Basically: minimize surfaces in dark oxygen rich areas where nitrification (nitraat making) can take place.


Die?

My previous tank. NO3 at 70. Was over 90 a couple of months earlier. Nothing dead, all growing.
1736934954057.png


Four months later compared to the previous picture. NO3 still 40. Acros starting to touch the water's surface...
1736935133960.png
Btw, how did you lower the nitrate to 40?
 

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