Nitrates sky high at 160ppm. Is me adding nitrogen causing this?

[Maxim5]

I have 20 gallon tank matured for 1 year. I just did a random test for nitrates and it's 160ppm. Does adding flourish nitrogen affect the reading or is this related to something like my bioload and other items? Please help.
I dose EI with the flourish line and do 50% water changes per week. I have about 20 rasboras, 1 siamese algae eater ,15 shrimp and a small pelco.
Have decent plant mass and co2 injection.

[Urban Aquaria]

The additional nitrogen ferts are basically adding more nutrients than what the plants can take up, so the excess nitrate levels naturally build up higher and higher over time (even with the recommended large 50% water changes when doing EI dosing).

In this case, since you've managed to detect the elevated nitrate levels, just reduce the nitrogen fert dosing amount accordingly and do additional water changes to reduce nitrates to a more manageable level. Its best to do the water changes in stages though, your fishes and shrimps have probably been accustomed to the high nitrate levels, so they have to be slowly acclimated back to lower levels.

Your existing bio-load seems okay for the tank volume, so i guess its just the accumulation of nitrates over many months... it could also be an indication your filter has not been cleaned for a while (lots of decomposing organic matter collected inside creating a nitrate factory), so it would be a good idea to keep up with filter cleaning and maintenance.

[Maxim5]

The additional nitrogen ferts are basically adding more nutrients than what the plants can take up, so the excess nitrate levels naturally build up higher and higher over time (even with the recommended large 50% water changes when doing EI dosing).

In this case, since you've managed to detect the elevated nitrate levels, just reduce the nitrogen fert dosing amount accordingly and do additional water changes to reduce nitrates to a more manageable level. Its best to do the water changes in stages though, your fishes and shrimps have probably been accustomed to the high nitrate levels, so they have to be slowly acclimated back to lower levels.

Your existing bio-load seems okay for the tank volume, so i guess its just the accumulation of nitrates over many months... it could also be an indication your filter has not been cleaned for a while (lots of decomposing organic matter collected inside creating a nitrate factory), so it would be a good idea to keep up with filter cleaning and maintenance.

Thanks, so do plants still need nitrogen if the nitrate level are consistently higher or medium? Or should I stop all nitrogen addition until the nitrate levels start to reach low levels?

[Shadow]

How much fert do you dose a week? With 50% weekly water change, it should not reach 160ppm.

[Maxim5]

I was dosing Seachem flourish line:

7 ml of nitrogen x4 per week
22ml phosphorus x4 per week
10ml potassium x4 per week

I used this calculator http://rota.la/ online to find out the EI value for the Flourish products. I does say to add it 2-4 times per week. Am I overdoing it?

I keep getting algae coming onto my Monte Carlo carpet. It's slowly getting darker and browner each day. See below:

[Shadow]

Roughly you are dosing 28ppm per week. Plant intake roughly 5ppm a day depending on quantity. With weekly 50% water change, It should not reach 160ppm. Have you check how many ppm after 50% water change?

[Maxim5]

Roughly you are dosing 28ppm per week. Plant intake roughly 5ppm a day depending on quantity. With weekly 50% water change, It should not reach 160ppm. Have you check how many ppm after 50% water change?

Yeah I did a 50% water change and I still have a reading of over 90ppm

[Shadow]

OK. That mean the tester is working. What soil you are using? ADA Amazonia? Don't worry about the algae is not cause by nitrogen overdose.

[Maxim5]

OK. That mean the tester is working. What soil you are using? ADA Amazonia? Don't worry about the algae is not cause by nitrogen overdose.

Yes, ADA Amazonia. I just finished a very heavy gravel cleaning, and I did find quite a bit of dead roots etc. Maybe that kept the nitrate high.

Do you think the brown/spotty algae on the monte carlo is related to too much light?

[Shadow]

Normally due to too much light or too long hour. But from he picture look like only the old leaf is effected, which is normal, I would not worry so much.

[Urban Aquaria]

Thanks, so do plants still need nitrogen if the nitrate level are consistently higher or medium? Or should I stop all nitrogen addition until the nitrate levels start to reach low levels?

Well, EI dosing is meant to create an environment whereby nutrients are non-limiting for plant growth... but its also an "estimate" method (not fixed) and is meant to be adjusted and further fine-tuned by different users based on different tank setups (as mentioned by Tom Barr).

The EI calculators generate generic dosage recommendations but they don't take into account what type of substrate used (ie. ADA aquasoil vs inert gravel/sand) or the type of bioload (ie. no fishes vs lots of fishes) or the plant types/density (ie. few slow growing plants vs lots of fast growing plants). So its just considered a base starting guide for the dosing regimen and then adjusted from there on based on the plants growth conditions.

In your case, just like in the example Shadow mentioned, the plants may just be consuming the nitrogen ferts, but leaving the nitrates created by livestock and feed un-used, hence excess nitrates just keep accumulating over time.

Even with 50% water changes, that only halves the existing nitrate levels, but as long as there are excess nitrates not being used up by the plants, they will still slowly increase higher every week.

For example, say nitrates are at 80ppm, after 50% water change, become 40ppm, but after 1 week, it builds back up slightly higher to 90ppm, then 50% water change again and it drops back down to 45ppm (but still higher than previous week after water change) and so on. Just a small 5-10ppm increase in excess nitrate levels every week will eventually result in 160ppm or more over the span of a few months.

A solution can be to just reduce the nitrogen fert dosing to half or quarter, and let the plants depend less on the fertilizer and start to actively use up the naturally occurring nitrates in the tank... the advantage here is you don't need to do additional water changes (save water and extra effort), just the normal weekly 50% water change as per normal, and the nitrate levels will steadily decrease as they are being consumed by the plants, so the change in parameters will be gradual, better for the livestock.

Do you think the brown/spotty algae on the monte carlo is related to too much light?

The algae on the monte carlo looks like green spot algae, they usually grow on leaves which are older or weak... perhaps it could be excess lights, though some people find that increasing phosphate level helps to reduce those algae appearing (may or may not work). The other option is to just remove the affected leaves or maybe try horned nerite snails, see if they can help clear some of those algae from the leaves.

[Maxim5]

Well, EI dosing is meant to create an environment whereby nutrients are non-limiting for plant growth... but its also an "estimate" method (not fixed) and is meant to be adjusted and further fine-tuned by different users based on different tank setups (as mentioned by Tom Barr).

The EI calculators generate generic dosage recommendations but they don't take into account what type of substrate used (ie. ADA aquasoil vs inert gravel/sand) or the type of bioload (ie. no fishes vs lots of fishes) or the plant types/density (ie. few slow growing plants vs lots of fast growing plants). So its just considered a base starting guide for the dosing regimen and then adjusted from there on based on the plants growth conditions.

In your case, just like in the example Shadow mentioned, the plants may just be consuming the nitrogen ferts, but leaving the nitrates created by livestock and feed un-used, hence excess nitrates just keep accumulating over time.

Even with 50% water changes, that only halves the existing nitrate levels, but as long as there are excess nitrates not being used up by the plants, they will still slowly increase higher every week.

For example, say nitrates are at 80ppm, after 50% water change, become 40ppm, but after 1 week, it builds back up slightly higher to 90ppm, then 50% water change again and it drops back down to 45ppm (but still higher than previous week after water change) and so on. Just a small 5-10ppm increase in excess nitrate levels every week will eventually result in 160ppm or more over the span of a few months.

A solution can be to just reduce the nitrogen fert dosing to half or quarter, and let the plants depend less on the fertilizer and start to actively use up the naturally occurring nitrates in the tank... the advantage here is you don't need to do additional water changes (save water and extra effort), just the normal weekly 50% water change as per normal, and the nitrate levels will steadily decrease as they are being consumed by the plants, so the change in parameters will be gradual, better for the livestock.




The algae on the monte carlo looks like green spot algae, they usually grow on leaves which are older or weak... perhaps it could be excess lights, though some people find that increasing phosphate level helps to reduce those algae appearing (may or may not work). The other option is to just remove the affected leaves or maybe try horned nerite snails, see if they can help clear some of those algae from the leaves.

Thanks for the insight. I'm starting to understand this way better. After multiple large water changes, I've finally managed to get my nitrates to 30ppm. The cherry shrimp and fish seem much happier now and come out. I'm going to cut back on the ferts and only dose 2x per week for now and see what happens.

[Shadow]

monitor your nitrate for couple of weeks, it may just because you disturb the soil.