Should I Dose Nitrates?

[atlfishes]

I read through a few topics and wanted some help thinking through this. I have an sps dominate reef tank and nitrates have been undetectable and phosphates .02-.04 using phosphorus ULR. I took an algae scrubber off line a month ago and currently have no macro algae.

One area I haven’t seen discussed is turning off the skimmer or cycling on and off. Is this not a viable option to increase nutrients?

That would leave live rock, filter socks and seachem matrix (sump) and water changes to do the heavy lifting.

 

[Brew12]

I read through a few topics and wanted some help thinking through this. I have an sps dominate reef tank and nitrates have been undetectable and phosphates .02-.04 using phosphorus ULR. I took an algae scrubber off line a month ago and currently have no macro algae.

One area I haven’t seen discussed is turning off the skimmer or cycling on and off. Is this not a viable option to increase nutrients?

That would leave live rock, filter socks and seachem matrix (sump) and water changes to do the heavy lifting.

My only concern with turning the skimmer off is air exchange. If I were going to go that route I would put in a large air stone to run during the times the skimmer was off. I've pulled my collection cup for a few days when I've wanted to raise nutrients, but I like having the big bubbler running.

 

[reefer4816]

i started dosing calcium nitrate i bought from amazon. i love it. it really does help.

what test kit are you using for nitrate?

 

[atlfishes]

Good point, how do we know if enough air exchange is occurring? My display is 265 gallons and sits on the main floor. Water cascades down to the basement and into two separate 50 gallon tanks, which then both flow through to sump and then back to main tank. Am I wrong to think this is plenty of air exchange?

I have Red Sea and Salifert nirtate test kits. I like the Red Sea better, but need to get another one since it's expired. Is there a better one?

Skimmer has been off for three days and during that time I've increased coral feedings (oyster feast and reef roids). I just finished testing and phosphates increased to .05, but still no nitrates. I haven't taken GFO offline and won't until I see phosphates start to drop. If only my phosphates increase, then this would not be my ideal outcome.

My Sodium Nitrates have arrived and I could start dosing. I don't want to manually dose daily, so that means dosing pump. A pump malfunction would probably be a certain crash. Any safeguards dosers use? I'd have it on an apex.

 

[Brew12]

Good point, how do we know if enough air exchange is occurring? My display is 265 gallons and sits on the main floor. Water cascades down to the basement and into two separate 50 gallon tanks, which then both flow through to sump and then back to main tank. Am I wrong to think this is plenty of air exchange?

I have Red Sea and Salifert nirtate test kits. I like the Red Sea better, but need to get another one since it's expired. Is there a better one?

Skimmer has been off for three days and during that time I've increased coral feedings (oyster feast and reef roids). I just finished testing and phosphates increased to .05, but still no nitrates. I haven't taken GFO offline and won't until I see phosphates start to drop. If only my phosphates increase, then this would not be my ideal outcome.

My Sodium Nitrates have arrived and I could start dosing. I don't want to manually dose daily, so that means dosing pump. A pump malfunction would probably be a certain crash. Any safeguards dosers use? I'd have it on an apex.

I honestly have no idea how much air exchange is "plenty" and I don't know how to measure it. That is why I prefer to defer to the safe side and keep my skimmer running. It's very possible that I worry about it for no reason.

 

[PatW]

The phosphates look good. You can dose nitrates easily enough.you can use spectracide which is used to remove stumps.you can usually get it at Home Depot. Or you can buy sodium nitrate on Amazon. I dose nitrates.

 

[Randy Holmes-Farley Verified Community Expert]

I read through a few topics and wanted some help thinking through this. I have an sps dominate reef tank and nitrates have been undetectable and phosphates .02-.04 using phosphorus ULR. I took an algae scrubber off line a month ago and currently have no macro algae.

One area I haven’t seen discussed is turning off the skimmer or cycling on and off. Is this not a viable option to increase nutrients?

That would leave live rock, filter socks and seachem matrix (sump) and water changes to do the heavy lifting.

It may be viable, but is not optimal, IMO. Aeration is a big benefit of a skimmer, and I'd hate to lose that just to increase nutrients.

I vote dosing, since it is easy to control.

 

[Randy Holmes-Farley Verified Community Expert]

Good point, how do we know if enough air exchange is occurring? My display is 265 gallons and sits on the main floor. Water cascades down to the basement and into two separate 50 gallon tanks, which then both flow through to sump and then back to main tank. Am I wrong to think this is plenty of air exchange?
.

I agree that "enough" is hard to quantify, but unless there is zero pH swing day to night, aeration is not "complete". Almost no one experiences that, and studies show many reef tanks drop below 100% saturation with O2 during the night.

 

[Mike Reef Addict]

Lol I just don't get the dosing nitrate part It's been awhile since I was in the hobby come back and people are adding what we used to work so hard to have at 0ppm nitrate and phosphate are why we came up with using mangroves and algae scrubbers.

I don't know whether to nod my head or shake it...

 

[Randy Holmes-Farley Verified Community Expert]

Lol I just don't get the dosing nitrate part It's been awhile since I was in the hobby come back and people are adding what we used to work so hard to have at 0ppm nitrate and phosphate are why we came up with using mangroves and algae scrubbers.

I don't know whether to nod my head or shake it...

We used to recommend low levels to mostly keep algae in check, and didn't usually have tools to drive it too low (and when we intentionally did, as in zeovit, we knew to dose foods and organics such as amino acids directly for corals).

Now, with things like organic carbon dosing, powerful ATS and algae reactors, sulfur denitrators, GFO, etc. people often go to far.

 

[atlfishes]

I agree that "enough" is hard to quantify, but unless there is zero pH swing day to night, aeration is not "complete". Almost no one experiences that, and studies show many reef tanks drop below 100% saturation with O2 during the night.

What do you think about just running the skimmer at night?

 

[reefer4816]

I would keep skimmer on 24/7. And dose with a doser. Your afraid of the doser malfunctioning and nuking the tank. This would be the same effect as if Alk was over dosed as well. So just use the same dosing method u do for Alk..

Secondly I would encourage u do as many doses per day as you can. I set my doser to dose 1 ml every hour. And then I just adjust my solution to be more or less potent depending how much nitrate is needed.

Dosing like this helps things stay stable. I found when I would hand dose once per day, my nitrate would climb to 5. And then 4 hours later back to 0.00. It was very disheartening. Spreading doses throughout the day helped keep it right where I want all day long.

 

[hatfielj]

I too found it funny/unbelievable when I first learned people were now dosing Nitrates AND Phosphates in some instances. BUT, I'm super glad this has occurred, because my current tank and my last tank both had undetectable NO3 and Phosphates and I didn't realize that was why my colors were pale at times. I used to ignore these readings and just blamed it on not feeding enough or something else. I also think this accounts for some of the mysterious STN that I've experienced in the past.
With my current system I've been very carefully monitoring NO3 and Phosphate and I now realize that without supplementation these would be dangerously low. I have a heavy fish load and I feed heavily, but it's not enough. I don't have any algae scrubbers and I only run a small amount of carbon occasionally to help remove any toxins that make their way into the tank. My skimmer is very efficient and I don't want to turn it off. So, I started dosing stump remover this week. It immediately caused my Phosphates to drop to undetectable levels as well, so I started dosing Phosphate as well. I can already tell my corals are happier. The colors are starting to look better and I'm getting better polyp extension. These are all small frags still since it's a new system. Most of these frags came from WWC or Jason Fox about a month ago. They were super dark/vibrant and slowly got pale over the first two weeks in my tank. Now that my nutrients are back up, they are starting to improve. I tested the water from both JFox and WWC when I got the frags. Both of them had super high nitrates (like above 15-25 ppm range). Their phosphates were in the 0.03-0.05 range. SO, I know this is a trick the pros are using to get the excellent colors. Will have to monitor these parameters closely though to make sure they don't get too high.

 

[Mike Reef Addict]

We used to recommend low levels to mostly keep algae in check, and didn't usually have tools to drive it too low (and when we intentionally did, as in zeovit, we knew to dose foods and organics such as amino acids directly for corals).

Now, with things like organic carbon dosing, powerful ATS and algae reactors, sulfur denitrators, GFO, etc. people often go to far.

Yeah so much has changed in the last 10-15 years since I got out and back in the hobby I'm basically running an oldschool berlin no sump with an oversized skimmer with some modern bells and whistles dosing pump LED lighing wave maker with the "new" wave pumps instead of powerheads when I do my 90g build with a custom stand I may add some reactors run a refugium etc

 

[Randy Holmes-Farley Verified Community Expert]

What do you think about just running the skimmer at night?

That's better, but I'd pick 24/7 and dosing inorganic nutrients if needed.

One other issue with 12 on/12 off is the water sitting in the skimmer might become stagnant in 12 h.

 

[jasonrusso]

I read through a few topics and wanted some help thinking through this. I have an sps dominate reef tank and nitrates have been undetectable and phosphates .02-.04 using phosphorus ULR. I took an algae scrubber off line a month ago and currently have no macro algae.

One area I haven’t seen discussed is turning off the skimmer or cycling on and off. Is this not a viable option to increase nutrients?

That would leave live rock, filter socks and seachem matrix (sump) and water changes to do the heavy lifting.

You never really said why you wanted to start dosing nitrates? Are you getting good growth and color? Maybe the nitrates are in balance and the corals are using all they need.

 

[Randy Holmes-Farley Verified Community Expert]

You never really said why you wanted to start dosing nitrates? Are you getting good growth and color? Maybe the nitrates are in balance and the corals are using all they need.

Undetectable nitrate risks dinos, and that alone may be sufficient reason to dose.

 

[Brew12]

Undetectable nitrate risks dinos, and that alone may be sufficient reason to dose.

I worry more about cyanobacteria when nitrates bottom out. I feel dino's are more common in phosphate deficient systems.

 

[TRock]

I worry more about cyanobacteria when nitrates bottom out. I feel dino's are more common in phosphate deficient systems.

I'd agree with that.

 

[Randy Holmes-Farley Verified Community Expert]

I just don't worry about cyano the way I'd worry about dinos.