High nitrate problem

[Poseidon9697]

It's hard to change that much water, even if you do a 50% water change it would only drop the nitrates to 50ppm. I would be concerned with the source of the issue. I would agree with possibly getting rid of the biobricks or washing them at least. Why not start (slowly!) carbon dosing to start lowering the nitrates?

 

[gbroadbridge]

It's hard to change that much water, even if you do a 50% water change it would only drop the nitrates to 50ppm. I would be concerned with the source of the issue. I would agree with possibly getting rid of the biobricks or washing them at least. Why not start (slowly!) carbon dosing to start lowering the nitrates?

Anaerobic decomposition within bio bricks and other media, reduces Nitrates rather than increases them.

 

[arking_mark]

All right. It seems the best course of action may be to change out alot of the water. I will vacuum the crap out of the sand bed and change water at same time. I will do multiple 30g water changes over the next week and then consider nopox in the longterm once things stabilize. Do you think I should consider greater CUC in the long run? It will be very difficult to add to the 150 because of the fish present (and to be added) but the 92g should be easy as no big predators in there. I also turned my fuge light to 24hrs and added filter socks which I will change daily

Since your tank inhabitants aren't stressed, I would recommend:

1. Sticking with your regular water changes and maintenance routine for now as 3 x 30gal water changes equals ~$45.
2. With money saved above, buy a Hanna nitrate tester and verify your readings. I never trust my eyes and the color test kits.
3. Assuming you still have elevated NO3, I would start DIY NOPOX...super slow.
4. Over time, I would simplify your filtration and get rid of the marinepur bricks, carbon filter, etc...Stick to simple mechnical filters, Fuge, UV, and Skimmer.

 

[sdreefer619]

Honestly been high for awhile but not this bad. No major changes. No livestock appears in distress

Honestly been high for awhile but not this bad. No major changes. No livestock appears in distress

30g is not enough. That’s not even 10%

 

[Chortanator]

Since your tank inhabitants aren't stressed, I would recommend:

1. Sticking with your regular water changes and maintenance routine for now as 3 x 30gal water changes equals ~$45.
2. With money saved above, buy a Hanna nitrate tester and verify your readings. I never trust my eyes and the color test kits.
3. Assuming you still have elevated NO3, I would start DIY NOPOX...super slow.
4. Over time, I would simplify your filtration and get rid of the marinepur bricks, carbon filter, etc...Stick to simple mechnical filters, Fuge, UV, and Skimmer.

It's better to do 1 large water change rather than 3 small ones so that the nitrates don't build up over time between the water changes.

 

[sdreefer619]

It's better to do 1 large water change rather than 3 small ones so that the nitrates don't build up over time between the water changes.

Unless they were done like every other day

 

[Randy Holmes-Farley Verified Community Expert]

I'm not really a fan of using big water changes to correct nutrient issues because it usually is less convenient and more expensive than other options unless the tank is quite small. it's also not every effective against phosphate due to the phosphate temporarily bound to rock and sand.

I'd personally just look to more export. Growing macroalgae is a good way. Have you ever dosing iron? Caulerpa can benefit from trace element dosing, maybe including manganese too.

Organic carbon dosing is also a good idea, IMO, because it does much more than just lower nitrate. It feeds many filter feeders.

 

[Dan_P]

I have been struggling with my tank lately.. It is a combined 280g system with 2 tanks to 1 sump. I noticed the beginning of dinos and noticed on test my nitrates are 100ppm on salifert test. My question is how do I lower this? Nothing has seemed to work and my phosphate is not proportionate at all imo. I run an oversized skimmer, small fuge full of Calurpa , UV, Activated carbon reactor 150lbs of LR and tons of marine pure bricks and balls. Bio load is honestly not intense at all eihter. Readings are-

Nitrate 100ppm Salifert
Phosphate 0.18 Hanna
Alk 7DKH Salifert
PH 8.14
ORP 388
Should I consider carbon dosing? Raising phosphate while carbon dosing? Something else?

Your system just needs an increased level of nitrogen (nitrate) export. Don’t expect to control nitrates with activated carbon or skimming. They are playing a smaller role. I assume the marine pure bricks are suppose to increase denitification capability (NO3 to N2), but they might not have the capacity you need.

Caulerpa removes nitrate, but how much depends on light intensity, micro nutrient availability, water motion and how much you have. If the Caulerpa is not doubling in size every week or so, it is underperforming.

Carbon dosing, vinegar or vodka, would be a cheap and easy way to increase the nitrate export capability of the system. If you had an automatic doser, even easier. If you follow the dosing schedule of the table on the internet, it is probably the one that has been incorrectly scaled. If you follow it, the increase in the dose will be too slow and you will never reach an effective dose, i.e., carbon dosing will appear fail.

 

[drosie]

Your system just needs an increased level of nitrogen (nitrate) export. Don’t expect to control nitrates with activated carbon or skimming. They are playing a smaller role. I assume the marine pure bricks are suppose to increase denitification capability (NO3 to N2), but they might not have the capacity you need.

Caulerpa removes nitrate, but how much depends on light intensity, micro nutrient availability, water motion and how much you have. If the Caulerpa is not doubling in size every week or so, it is underperforming.

Carbon dosing, vinegar or vodka, would be a cheap and easy way to increase the nitrate export capability of the system. If you had an automatic doser, even easier. If you follow the dosing schedule of the table on the internet, it is probably the one that has been incorrectly scaled. If you follow it, the increase in the dose will be too slow and you will never reach an effective dose, i.e., carbon dosing will appear fail.

What would be a good starting dose for carbon? I made a vinegar vodka mix that is supposed to be fairly close to nopox that I got off another forum. I will dose some nutrients as the calurpa is nowhere near doubling weekly. Also yes the marine pure bricks are in 2 seperate sections. I have one in a high flow area of sump for increased bacteria housing where the LR in the 150g is minimalist due to the livestock in there and wanting to leave lots of open swimming room. The rest are in the fuge in a “lower flow section” to try to act as denitrifying objects but I honestly think the flow is too great through the fuge to really do that job.

 

[arking_mark]

What would be a good starting dose for carbon? I made a vinegar vodka mix that is supposed to be fairly close to nopox that I got off another forum. I will dose some nutrients as the calurpa is nowhere near doubling weekly. Also yes the marine pure bricks are in 2 seperate sections. I have one in a high flow area of sump for increased bacteria housing where the LR in the 150g is minimalist due to the livestock in there and wanting to leave lots of open swimming room. The rest are in the fuge in a “lower flow section” to try to act as denitrifying objects but I honestly think the flow is too great through the fuge to really do that job.

Nutrient and Alk increase when a tank matures

So I have a theory on why some tanks see an increase in Alk and nutrients when they mature. My tank is just about a year old. Prior to this month, Alk has been pretty consistent and nutrients running very low. This month my Alk and nutrients have started to rise. My theory: Substrate and...

www.reef2reef.com

 

[BrotatoSalad]

I'm not really a fan of using big water changes to correct nutrient issues because it usually is less convenient and more expensive than other options unless the tank is quite small. it's also not every effective against phosphate due to the phosphate temporarily bound to rock and sand.

I'd personally just look to more export. Growing macroalgae is a good way. Have you ever dosing iron? Caulerpa can benefit from trace element dosing, maybe including manganese too.

Organic carbon dosing is also a good idea, IMO, because it does much more than just lower nitrate. It feeds many filter feeders.

I’m in this camp as well. Large water changes are an expensive option, and if stability is the name of the game this isn’t they way. If the tanks are healthy outside of a big number I’d look at your water change method, rather than increasing the volume.

Are you just draining water and replacing with clean? Or are you blowing off the rockwork and getting into your sand bed and vacuuming?

If not, try picking a section of sand in your water changes and vacuum it. Next wc blow off parts of the rockwork and siphon out what you can. When the return pump is back on and the tank clears up change out your mechanical filtration to get the stuff missed out of the tank. Then hit the sand on the next and so on.

Start carbon dosing slowly and chip away at that number. If everything is healthy looking I don’t see any reason at all to perform a large water change.

When I was doing tank maintenance this was the ticket in a similar sized system that had been setup for 4 or 5 years. Took a month or two, but the number came down and the tank was better for it. Best of luck!

 

[KilianSP]

I also turned my fuge light to 24hrs

Sounds good, doesn´t work well. i tested on my macros (caulerpa prolifera and taxifolia) they grow when the lights go off. you can see that when the lights start at the morning, they have a white edge at the leafe, thats the grow. Mine grew better with 12 on 12 off, than 24 on, you could try 20 on 4 off.

filter socks which I will change daily

i change 2 times a day, my skimmer has almost nothing to do.

To the salifert Nitrate test, take 5ml of tank water, 5ml RODI water, mix it well, then take from the mixture 1ml and test it. if it shows 50mg, than you got real 100mg.
my salifert showed 25-10 mg, my photometer read 7mg, so salifert isn´t that accurate. if i want to get accurate results with salifert, i mix it with rodi, 1:1, or 1:2 or 1:3 and then double, triple the readings

 

[Dan_P]

What would be a good starting dose for carbon? I made a vinegar vodka mix that is supposed to be fairly close to nopox that I got off another forum. I will dose some nutrients as the calurpa is nowhere near doubling weekly. Also yes the marine pure bricks are in 2 seperate sections. I have one in a high flow area of sump for increased bacteria housing where the LR in the 150g is minimalist due to the livestock in there and wanting to leave lots of open swimming room. The rest are in the fuge in a “lower flow section” to try to act as denitrifying objects but I honestly think the flow is too great through the fuge to really do that job.

Here are some guidelines for dosing. Don’t forget to pay attention to how fish and inverts respond to each dose increase.

With a vinegar dose of about 1 mL/gallon, I have observed rapid nitrate reduction and white slime build up. Use this as your approximate final target. For vodka, that corresponds to roughly 1/8 mL/gallon. For a mix of vinegar and vodka, take the weighted average of 1 and 1/8.

Dose daily.

Shoot for at least 6 weeks to reach the target dose, but take longer if the fish and inverts seem to be stressed. If you want to go slower at the start to gain confidence that nothing bad is happening, that’s OK. Whenever increasing the dose, wait at least two days before increasing it again, four days to be super safe, just to make sure fish and inverts are OK. There is anecdotal evidence that vodka and NOPOX dosing are associated with cyanobacteria growth. Be on the lookout.

At higher doses watch for pH drops and consider splitting the dose into smaller portions. Again, fish and inverts should let you know if you are ramping up the dose too aggressively or you need to split the dose further.

Start decreasing the dose as you near your desired NO3 level. When the NO3 starts to increase, you went pass the maintenance dose. If the Caulerpa is growing well, the maintenance dose might be 0 mL.

 

[wculver]

I have been struggling with my tank lately.. It is a combined 280g system with 2 tanks to 1 sump. I noticed the beginning of dinos and noticed on test my nitrates are 100ppm on salifert test. My question is how do I lower this? Nothing has seemed to work and my phosphate is not proportionate at all imo. I run an oversized skimmer, small fuge full of Calurpa , UV, Activated carbon reactor 150lbs of LR and tons of marine pure bricks and balls. Bio load is honestly not intense at all eihter. Readings are-

Nitrate 100ppm Salifert
Phosphate 0.18 Hanna
Alk 7DKH Salifert
PH 8.14
ORP 388
Should I consider carbon dosing? Raising phosphate while carbon dosing? Something else?

At one time I had issues with nitrate and even unexplained spikes which I think was a combination of many things.

To start, the salifert tests were running me astray for nitrate. I would suggest having another test such as the red sea one which has really worked well and had reproducible results.

I ran marine pure and bio balls for years and I'm unsure if there was really any use in having them. I've actually taken all that out today without any noticeable difference.

What I did to stabilize nitrate and even phosphate was to run chaeto in my fuge with a 150 watt grow light and added a bio pellet reactor that feeds directly to the skimmer. The bio pellet reactor took around 4 weeks to start working but it was aggressive when it did. I actually bottomed out nitrate in the first round so you'll have to be careful with that considering the low stocking also. I have a 250 gallon setup and run 2 cups of bio pellets in the reactor. I still have to occasionally add nitrate so I test regularly. Then every few months I run GFO in a filter bag to reduce phosphate based on need.

You have to test daily around the four week mark. Once it starts reducing nitrate it goes fast. You'll also have to keep a close eye on the skimmer because it'll start boiling over easier with all the extra bacteria. Ultimately though it has given me a very stable nutrient processor.

 

[drosie]

Alright, I did a deep clean of sandbed, added nopox on a doser at 30ml a day after running at 20ml for about a week. I also got a ton of rock that I just bleach cured that I'm figuring out what to do with next, dialed the skimmer to skimmer a little wetter, harvested most of my Calurpa to let it start growing back. I also got a large hob fuge I plan on throwing chaeto in. Hanna nitrate checker being ordered soon as well. Salifert test looks less dark but still over 50 and phosphate was up to 0.3