Nitrate dosing experiences

BradB

Active Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 27, 2009
Messages
443
Reaction score
248
Review score
+0 /0 /-0
Location
Hudson
My tank has ran with escalating phosphate and near zero nitrate over the past few years. I experimented in the past dosing stump remover, which worked well putting my Nitrates where I want them (3-5ppm) and lowering phosphate - however my corals looked terrible. I was dosing large amounts and thought maybe going slower would help, but further experiments showed dosing less still made my corals worse than not dosing at all. By my calculations, Potassium should not have been a problem after water changes.

I completely gave up the idea of dosing Nitrates until this spring, when I bought a bunch of frags from one of the more successful SPS tanks in Ohio and the owner credited part of his success on Nitrate dosing. He was using Sodium Nitrate, and further reading on the forum supports that may work better than the Potassium Nitrate in stump remover.

I bought Reagent grade and dosed 1.3g into my approximately 1000 liter system for the first time today - approximately 1ppm NO3. Based on my past experience, this should do very little if anything at all. I plan to keep adding that level each day until the end of August, and up it in September if I don't notice any difference.

I've found lots of threads on this, but most talk about the math to know how to raise a certain ppm, or what product to buy - and almost all by people who aren't dosing but plan to start. I haven't found much of anything on anyone either dosing small amounts daily for the long term, large amounts for a quick one time fix, or people who tried this .
 
Avast

fishface NJ

2500 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 27, 2019
Messages
3,954
Reaction score
23,651
Review score
+0 /0 /-0
Location
Morganville, New Jersey and Cape Coral, Florida
I dose a small amt every few days but just enough to my NO3 at 2 or 3ppm. If you want your NO3 as an example at 5ppm, do it over a course of 14 days....raise it slowly. Here is a cal if you don't have one...http://www.theplantedtank.co.uk/calculator.htm

What test kits are you using for NO3 and PO4?
 
Last edited:

Reefer_punk

Community Member
Review score
+0 /0 /-0
View Badges
Joined
Jan 8, 2020
Messages
68
Reaction score
300
Review score
+0 /0 /-0
We add 2ml no3 and 4 ml po4 daily to keep it measurable. Doing this for over more than a year. Dosing no3+ and po4 + from DSR
20210731_152326-01.jpeg
 

Dan_P

2500 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Sep 21, 2018
Messages
2,534
Reaction score
2,511
Review score
+0 /0 /-0
My tank has ran with escalating phosphate and near zero nitrate over the past few years. I experimented in the past dosing stump remover, which worked well putting my Nitrates where I want them (3-5ppm) and lowering phosphate - however my corals looked terrible. I was dosing large amounts and thought maybe going slower would help, but further experiments showed dosing less still made my corals worse than not dosing at all. By my calculations, Potassium should not have been a problem after water changes.

I completely gave up the idea of dosing Nitrates until this spring, when I bought a bunch of frags from one of the more successful SPS tanks in Ohio and the owner credited part of his success on Nitrate dosing. He was using Sodium Nitrate, and further reading on the forum supports that may work better than the Potassium Nitrate in stump remover.

I bought Reagent grade and dosed 1.3g into my approximately 1000 liter system for the first time today - approximately 1ppm NO3. Based on my past experience, this should do very little if anything at all. I plan to keep adding that level each day until the end of August, and up it in September if I don't notice any difference.

I've found lots of threads on this, but most talk about the math to know how to raise a certain ppm, or what product to buy - and almost all by people who aren't dosing but plan to start. I haven't found much of anything on anyone either dosing small amounts daily for the long term, large amounts for a quick one time fix, or people who tried this .
Something to consider. When you dose NO3, it drives organism growth which means other nutrients are taken up faster and possibly become depleted such as trace elements.
 
BRS

Nick Steele

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Apr 28, 2019
Messages
2,028
Reaction score
2,002
Review score
+0 /0 /-0
Location
Port St. Lucie
I’ve had to dose (phos and nitrate) my tank due to Dino’s. Nitrates really didn’t take all that long to go up maybe a week to register 10ppm (I was dosing 5ppm daily). After a week it went down to 5ppm but has stayed relatively steady there over the past month. I’ve had to dose maybe twice since then to keep it at 5ppm.

Also I’m using neonitro for the moment but have sodium nitrate on hand to make my own mixture once it runs out.
 
OP
B

BradB

Active Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 27, 2009
Messages
443
Reaction score
248
Review score
+0 /0 /-0
Location
Hudson
I dose a small amt every few days but just enough to my NO3 at 2 or 3ppm. If you want your NO3 as an example at 5ppm, do it over a course of 14 days....raise it slowly. Here is a cal if you don't have one...http://www.theplantedtank.co.uk/calculator.htm

What test kits are you using for NO3 and PO4?
I use Hanna ULR for PO4 and Salifert for NO3.
 
OP
B

BradB

Active Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 27, 2009
Messages
443
Reaction score
248
Review score
+0 /0 /-0
Location
Hudson
Sounds like chasing numbers. Where are they currently?
15ppb Phosphate and no measurable NO3.

Phosphate will creep up over time and only goes down with water changes and GFO - both expensive ways of lowering it, although I should probably do more water changes anyway.

As I wrote, part of this is chasing other people's success. They dose NO3 and have better tanks.

I have more nuisance algae than I'd like, and coral growth is slower than it should be.

I've had a reef for 20 years. Over that time, the best tanks I've had have all had measurable (in some cases high) NO3 and low Phosphate without doing anything on my part to lower Phosphate.
 
OP
B

BradB

Active Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 27, 2009
Messages
443
Reaction score
248
Review score
+0 /0 /-0
Location
Hudson
We add 2ml no3 and 4 ml po4 daily to keep it measurable. Doing this for over more than a year. Dosing no3+ and po4 + from DSR
20210731_152326-01.jpeg
Is that 2.8 ppm (0.72ml / 100l = 1 ppm) NO3 and 400 ppb Phosphate (0.1 ml / 100 l = 0.01 ppm) per 100ml? How large is the tank? That seems like a lot of Phosphate.
 
OP
B

BradB

Active Member
Review score
+0 /0 /-0
View Badges
Joined
Aug 27, 2009
Messages
443
Reaction score
248
Review score
+0 /0 /-0
Location
Hudson
Something to consider. When you dose NO3, it drives organism growth which means other nutrients are taken up faster and possibly become depleted such as trace elements.
Yes, specifically Phosphate should go down, and if it works, Ca and Alk because the corals are growing. I dose 2 part. Water changes and ICP tests should keep everything else under control.
 
Reef Chasers Aquaculture

East1

Community Member
Review score
+0 /0 /-0
View Badges
Joined
Sep 20, 2020
Messages
57
Reaction score
166
Review score
+0 /0 /-0
Location
London
IMO if you need nitrogen it's better to dose urea, or amino acids, or an alternative like Seachem Synthesis. Nitrate inhibits coral growth when high, shown in a couple studies on the growth rate of corals, counter to phosphate which doesn't adversely affect coral growth
 

Randy Holmes-Farley

Reef Chemist
Review score
+0 /0 /-0
View Badges
Joined
Sep 5, 2014
Messages
45,836
Reaction score
35,077
Review score
+0 /0 /-0
Location
Arlington, Massachusetts, United States
IMO if you need nitrogen it's better to dose urea, or amino acids, or an alternative like Seachem Synthesis. Nitrate inhibits coral growth when high, shown in a couple studies on the growth rate of corals, counter to phosphate which doesn't adversely affect coral growth

Have you ever seen a study on whether urea is better than nitrate?
 

Randy Holmes-Farley

Reef Chemist
Review score
+0 /0 /-0
View Badges
Joined
Sep 5, 2014
Messages
45,836
Reaction score
35,077
Review score
+0 /0 /-0
Location
Arlington, Massachusetts, United States
I also own a 100 gal freshwater high tech plant tank too. I dosed Seachem Nitrogen for the Nitrogen supply for the plants. Part of the ingredients do contain urea.

I know. Seachem has it. That doesn't mean it is desirable. :)
 
AS

jda

7500 Club Member
Review score
+0 /0 /-0
View Badges
Joined
Jun 25, 2013
Messages
9,447
Reaction score
13,460
Review score
+0 /0 /-0
Location
Boulder, CO
Never seen any studies on urea, but there are some on ammonia/ammonium that provide nitrogen for micro algae whereas nitrate does not unless converted by the host. I have dosed ammonium before when I don't have enough fish to feed which appeared to help the corals like feeding would (anecdotal). Macro algae all appears to use nitrate directly.
 

East1

Community Member
Review score
+0 /0 /-0
View Badges
Joined
Sep 20, 2020
Messages
57
Reaction score
166
Review score
+0 /0 /-0
Location
London
Have you ever seen a study on whether urea is better than nitrate?

I have read one that pointed in this direction, but I formed the opinion from just experimentation and from reading comments from Lasse and Hans Balling on here.

The study in question referenced elevated nitrate having an effect on thermal tolerance of acroporids

In particular, nitrate (NO3−) enrichment reduces thermal tolerance while ammonium (NH4+) enrichment tends to benefit coral health. The biochemical mechanisms underpinning the different bleaching responses of corals exposed to DIN enrichment still need to be investigated. Here, we demonstrated that the coral Stylophora pistillata underwent a severe oxidative stress condition and reduced aerobic scope when exposed to NO3− enrichment combined with thermal stress.


Additionally, there is another study that relates thermal stress and photoinhibition as a function of flow rates which seems to imply that net energy and flow must be balanced and excess nitrate distrupts this balance.

Moreover, experiments involving sequential light oscillations (500/20 and 1000/20 µmol photons m–2 s–1) at 3 flow regimes, <3, 10, and 20 cm s–1, on a time scale ranging from hours to days, revealed water-velocity-dependent reductions of dynamic photoinhibition. These results, on time scales ranging from minutes to weeks, confirm that reduced water flow amplifies photodamage of algal photosynthesis under strong irradiance, which in turn affects coral tolerance to strong irradiance and temperature.

 

Randy Holmes-Farley

Reef Chemist
Review score
+0 /0 /-0
View Badges
Joined
Sep 5, 2014
Messages
45,836
Reaction score
35,077
Review score
+0 /0 /-0
Location
Arlington, Massachusetts, United States
Never seen any studies on urea, but there are some on ammonia/ammonium that provide nitrogen for micro algae whereas nitrate does not unless converted by the host. I have dosed ammonium before when I don't have enough fish to feed which appeared to help the corals like feeding would (anecdotal). Macro algae all appears to use nitrate directly.

I agree that ammonia dosing may be preferable to nitrate dosing, although with more overdose risks:

 

Randy Holmes-Farley

Reef Chemist
Review score
+0 /0 /-0
View Badges
Joined
Sep 5, 2014
Messages
45,836
Reaction score
35,077
Review score
+0 /0 /-0
Location
Arlington, Massachusetts, United States
I have read one that pointed in this direction, but I formed the opinion from just experimentation and from reading comments from Lasse and Hans Balling on here.

The study in question referenced elevated nitrate having an effect on thermal tolerance of acroporids




Additionally, there is another study that relates thermal stress and photoinhibition as a function of flow rates which seems to imply that net energy and flow must be balanced and excess nitrate distrupts this balance.




Thanks.
 
Aquarium Specialty - dry goods & marine livestock

Speaking of your latest coral purchase...

  • It was a GREAT deal

    Votes: 39 48.1%
  • It was a good deal

    Votes: 19 23.5%
  • It was nether good nor bad

    Votes: 17 21.0%
  • It was a bad deal

    Votes: 4 4.9%
  • Other (please explain)

    Votes: 2 2.5%
GHL Advanced Technology
Top