New 73 gallon tank setup
 

I have decided to run an experiment with my new tank and to see what adding nitrates to the tank will do.

I have a new tank I started last fall. The tank is the 73 gallon reefer from red sea. The tank has been running for about 6 months. I am running a Tunze doc 9410 skimmer. I have 2 giro 230's running for water motion and have a 48" ATI hybrid for lighting. I am using GFO to control my phosphates. And I though all other perimeters are good. I am keeping primarily SPS. I have had reef tanks for more than 20 years so I have a little bit of experience.
I have a low bio load and had to work hard to keep the phosphates down. I do not feed a lot so I was wondering what was going on. I have no algae growth. I have hundreds of Strombus sp. snails that keep any algae growth under control.

I am noticing that my corals are growing well but they do not have great coloration. I have a 40 gallon reef tank that I have had set up for 15 years with a deep sand plenum. When the corals were in this tank they had great colors but once I moved them to the large tank the colors have faded. I am moving the 40 gallon tank downstairs and will make a frag tank out of it.
My nitrates are at 0 on my reefer. I have never had even a slight bit of colour on my test. I am using a Redsea Pro nitrate test kit.

Last week I was talking to Gregzz4 and he told me that my problem with the phosphates are due to my 0 nitrates. If I raise my nitrates my phosphates will drop and my corals will colour up better. Being old school I always thought that the goal of reef tanks was to keep the phosphates and the nitrates at 0.

I have been doing some research and there is a lot of good information on the web in regards to nitrate dosing. Because I have a low bio load and I do not feed much my system is using up the nitrates faster than I am adding them or the fish are producing them. This is not the case with most systems, most systems over feed and have high levels of nitrate, thus the need for nitrate reduction methods.

I have read up on the Redfield ratio. Basically most marine biomass have a C:N:P ratio of 106:16:1. Being an Arborist I understand these ratios and it all makes sense. My Nitrogen Phosphorus ration is way off. Most people suggest just feeding more or adding more fish to raise my nitrates. That would work except that I would also raise my phosphate. When the ratios are off and you have high nitrates and phosphates you get nuisance algae. The great thing about my system is because of the low fish bioload I can raise my nitrates without raising my phosphates.

My goal is to get a nitrate level of around .5 to .8ppm nitrate. There are several products that you can use to raise your nitrates. Amino Acids are nitrate based. But you would have to add a lot of Amino acids to get the nitrates up. I have decided to use KNO3. I still dose amino acids as well.
According to Randy Holmes-Farley "Dissolve 10 grams potassium nitrate in 1 liter of fresh water. That 10 grams contains 6.14 grams of nitrate, so that solution is 6,140 ppm nitrate.

If you add 1 ml of the solution per 2 gallons of tank water volume, that will boost nitrate by 0.8 ppm nitrate.
I have started by adding 5mls of this solution twice a day. I am monitoring my nitrate daily. I do not want to raise my nitrate levels too quickly. From what I have read is the corals respond very quickly to an increase of nitrogen. I would add some pictures of the tank and the corals as they are now but I haven't figured out how to do it.

DIY ferts calculator
 

If you want exact measurements for ferts try https://rotalabutterfly.com/nutrient-calculator.php

I have used it for KNO3 for my planted tanks before, works great

Sounds weird but there are a lot of threads online about adding tree stump remover to raise nitrates, I've been doing some searching online in other forums and decided to order some from the states. My nitrates were undetectable until I dosed a lot of dirty food and left the skimmer off for a couple days (accidental) so now I am going to try and dose some slowly and raise the nitrates up abit.

NKO3
 

If by raise your nitrates your mean add KNO3, it should be very easy to find in BC. Pretty sure its a controlled substance, importing may be difficult/risky

Not really since it's already at point Roberts just got to go drive it over. A friend was using the planted stuff to raise nitrates but had negative results it was seachem so I decided not to go that route.

I purchased my KNO3 from Patrick at Canadian aquatics he lives in Richmond. Charges $5 a pound. He requires your drivers license and a reason for use. Has to record everyone that buys it.

It is a controlled substance in Canada and you might have problems at the border

I have attached a picture of the tank as of March 30. If this works I will attach some pictures of some corals before I began adding nitrates to the tank.
Attachment 15805

Seems to have worked.
The first coral is a Red Planet. Currently the polyps are light pink with almost no green in the body. When it was in my other tank it was dark red with a strong green colour. I have it situated lower in the tank
Attachment 15806
The second coral is a Pearl Berry. Very little blue in the color just seems faded out. There is a Blue Matrix in the back ground it is mostly brown with only a hint of blue. I have them situated mid tank.
Attachment 15808
The third coral is a Needle in the Haystack. Very pale coloration, lower in the tank.
Attachment 15807

I tested my tank today after adding 10ml's of the KNO3 mixture I prepared twice a day for the past 3 days.

SG:1.026
NO3-still 0 not even a tint of pink
PO4-.01ppm
Temp- 80f
Ca-410ppm
Alk dkh-9.7
Mag-1410ppm
K-400ppm
I have been monitoring the tank closely for any signs of stress, algae growth or changes and have seen nothing. I was wondering about the test kit for nitrate so I tested it against a known value (.6ppm) for KNO3 mixed in RO water and the test kit was bang on.

Looks like I have to increase the KNO3 levels as my tank is using it up as fast as I can add it. (good thing). I will double my dosage rate and report back in a few days.

Seeing as I am adding a lot of KNO3 I have been looking for a purer source as I am concerned about what else is in my KNO3. I have found a chemical company in Vancouver area that sells reagent grade 500 grams of for $27. As 500 gram of the stuff would likely be enough to last me several years even at a much higher dose.

My goal is to create an equilibrium within my tank nitrate to phosphate of around 16 to 1. The amount of K in the solution will not even slightly affect the total K in the tank as we are talking about 400ppm as per the nitrate levels of less then 1ppm.

KNO3
 

I remember buying 25kg bags of KNO3 for $50 back in my model rocket making days(hydroponics grade)

All these idiots trying to blow up the world have made this stuff hard to find :onfire:

As I said before I am not using any kno3 as I am not sure what it will do in terms or growing algae... I went to point Roberts on the weekend and picked up some stump remover, I am going to do some reading before mixing it up and putting it on the doser. I also tested my nitrates last week and finally after adding some dry rock that was not cured I have some readings of nitrates but it is in the range of 0-5ppm so I will continue to test and as it falls I will add some of this nitrate.

How long have your sps been in the tank, they look pretty pale... hopefully with kno3 you will see some better colouration in the coming month. Usually sps will look bleached then get brown then colour up. Good luck!

The pictures are not great. They are not as pale as they appear in the photos. The corals have been in my tank for about 1 to 3 months. I have about different 20 sps. I have shown the pictures of the palest ones. All the corals are growing well, they just are paler then I have seen elsewhere.

Even with adding nitrates I still can't get a reading. I will continue to do so. I am also feeding the corals and adding amino acids every day.

Reef tank long time experts like Julian Sprung, Sanjay Joshi, Jason Fox, Elegance Corals, Brad Syphus and other top sps coral collectors are keeping their nitrates at level above 5ppm and some of them up to 50ppm.

There are some horror stories using stump remover, check some forum treads. It works for some but didn't on others.

For me, KNO3 is a better choice to raise your nitrate. It will not only raise your NO3 but will also raise your Potassium (K) level a little bit which is good for coral coloration. You also need to check your K level to make sure it is on the 400 range. It is also easy to dose and calculate the levels, check on the article written by Randy Homes Farley. But again, dose slowly...

Hey man I hear you on that, definately horror stories on a lot of stuff. Equiptment, salt you name it. Anything I do I always try abit and wait awhile to see the coral reactions.

How often are you doing waterchanges and how much?

Changing water about 10 gallons every second week on a 80 gallon system. This was more an effort to reduce phosphates that had gotten really high. Using only RO DI water newer filters. I was only lightly feeding and have a low fish bio load (5 fish). I was using a lot of GFO to help reduce phosphates. I have never registered Nitrates. It was Gregzz4 that told me the 0 nitrates is the problem.

Almost the same issue with me, no no3 and sometimes lots of po4. The colours on my sps are awesome tho so can't complain but the po4 won't go down without no3 they drag each other down....

How's your bioload, how about your feeding? You must be adding enough nitrates in your food that keeps the corals fed and healthy but not enough to stabilize your Phosphates.

Your system is likely using up any nitrates that you add.

I have about 25 fish and feed 3-5x per day dirty food like pei mysis plus coral food so definately a lot of feeding.

The heavy feeding is why you have enough nitrates to keep the colours in your corals but not enough to control your phosphates.

I have always been a light feeder of my fish, as there is enough going on in the tank to keep them healthy. My only concern with adding a lot of food is I would be adding more phosphate and would not achieve that balance. That is why I am now adding the KNO3 and amino acids (which are all nitrates) and not adding phosphates.

Still no nitrates measurable in my system. I will go to 10mls 3 times a day plus daily amino acid additions.

True to the above, that is why I do 5g wc every 3 days. I keep anthias and they like to eat, plus some of the other fish need to be fattened up. Once they are overweight I'll back off on the feeding. I am not that concerned with po4 as it is easily controlled via rowaphos. If I can increase the nitrates it should drop to po4 further. I stated in my journal I noticed my sps with the best growth when po4 was hovering in the .04-.10 range any higher and the growth slows down drastically.

After 4 days of dosing KNO3 I finally have a readable nitrate level in the tank. .25ppm :biggrin:. I have been adding 35mls of the KNO3 solution daily (that is the equivalent of almost .8ppm of nitrate for my tank volume daily). I may be imaging things but a few of the corals appear to have a little more colour. Too early to be certain. I will continue to add the same amount of KNO3.

My calcium level has dropped 50ppm since Saturday. I have even been adding a bit more calcium in the past week because I felt 410 might be a little low. My only guess is nitrate was the limiting factor in the growth of corals and coralline algae. Once nitrates are available these processes have kicked in using more of the calcium. I will double my dose of calcium to try to get it back on track.

I had heard that dosing KNO3 raises alkalinity so I have reduced my buffer addition in half over the past 4 days and I am stable at 9dkh

I think you are on the right track.

Sounds like it's working well Glen(?)
For the record, Ryan Erickson gets credit for this. I read something he posted awhile back and picked his brain about it. He wrote about adding NO3, and while talking with Jon @ J&L he suggested Seachem's Nitrogen. Ryan may have also mentioned it, but I don't recall ... it was last year :biggrin:

@ Tang Daddy;
I used Seachem Nitrogen and had no issues due to their product. I did add too much too fast though. This dropped my PO4 so quickly that my corals were a bit PO'd for some time after.

And for everyone;
Looking back through my records, I started dosing 2ml/day back in early November. Nothing happened for days so I bumped it to 5ml/day. Couple days later I finally read 5ppm NO3. PO4 dropped from 0.06 to 0.03. A week later NO3 was up to 10 and PO4 was 0. Then the tissue recession and bleaching started ...
Had I known there would be such a drastic effect I would have tested daily.

I pulled my GFO and PO4 rose back to 0.04. I continued to test/dose until PO4 was stable, then stopped dosing. I also pulled my Carbon.
This was early January and I haven't dosed any Nitrogen since.
March 30th Hanna told me PO4 is @ 0.01 and Salifert reported 0ppm NO3.
It's been 2 weeks since a 25% WC (due tonight) and I just tested before another WC;
PO4 is @ 0.03 and NO3 is @ 0ppm.

Currently I only have 4 fish in the DT, plus a couple shrimps and some hermies. They are fed pellets for lunch, and I rotate between 2 different kinds of flakes or a cube of frozen for dinner. Plus nori a couple times a week. When I feed, it's like it's snowing in the tank so there should be higher readings ... :noidea:
If I feed them any more they'll pop !!
I have some fish in QT and will be doubling my fish load in the near future. This will cause some new testing/dosing, but I hope it will help increase my levels enough to get some NO3 and PO4 readings without having to tweak things too much.

Hope this helps someone, and good luck Glen

From what I had read on the internet the Flourish Nitrogen contains KNO3 and Urea. I wanted to use a source, Pure KNO3, where I could control the exact amount of Nitrate I wanted and really didn't want to add urea.

My tank has been at between .5 to .75ppm NO3 and phosphates are steady at .02ppm. I have been adding 35mls per day of the mixture and it appears to be working. The colours are beginning to look better. However the calcium uptake has gone through the roof and I have had to triple my calcium additions. I am assuming that growth was limited by the very low nitrates and now that they are there growth has kicked in. Too early to measure effectiveness.

I am still using GFO. I will stop using GFO if my phosphates drop too low.

I might still go higher with my nitrates although I really want to take this slow. I will probably keep my nitrates at around 1 for a few weeks and see what happens before I will go higher.

What are you using to test NO3?

I am using Red Sea Pro Nitrate Test. I made up a batch of NO3 .8ppm calibration solution using Randy Holmes-Farley recommendations and my test kit was bang on.

I have been able to maintain my nitrates at .5ppm for 5 days. I have been adding 40mls of the KNO3 solution daily.

My phosphates have dropped off the chart. I am almost using no GFO and my phosphates were .003ppm. Still too low. Before I started raising my nitrates my phosphates were over 2ppm and I was using a ton of GFO to keep it respectable. So just for controlling phosphates this is a win.

The colours of my corals are getting better.
This blue matrix was brown before I started adding nitrates.
Attachment 15823
This red planet was very pale
Attachment 15824
This Hawkins was dull
Attachment 15825

These pictures were taken from above, the other picture were taken from in front and I fixed the white balance on my camera. They are still not show quality but the colours have improved quite a bit.

I can't get my phosphates under 0.25ppm even with the use of gfo in a reactor and Foz Down. I can't complain as my corals have nice colours and decent growth. From the sounds of it your nitrates are registering and your Cora are improving which is great. Keep us posted.

After 2 weeks of adding KNO3, now adding 60mls/day, which equates to adding 2ppm per day of nitrate for my 73 gallon tank.

I am now at 1.5ppm NO3 and phosphorus is 0 using Hanna ULR meter. I was using about a half a cup of GFO. I have now turned off the GFO because I do not want my phosphorus at 0.

I was needing to run at least 3 cups of GFO to keep my phosphorus below .03ppm before I started adding KNO3. If I didn't my phosphorus would hit .3ppm very quickly.

My tank appears to be using close to 2ppm nitrates to maintain a nominal nitrate level in the tank. I like my current level of nitrates however it appears the higher I go the lower the phosphates get. I think this is going to be a bit of a balance game, lets see what happen now that I turned the GFO reactor off.

What I have noticed in my tank with the higher nitrates is better growth and color of the corals, not quite as good as I want but my coralline algae is growing like nuts, hence the larger draw of Calcium.

I caution anyone thinking that they can control their phosphates by adding nitrates. My situation was a particular situation where I have a low bio load, feed lightly, strong skimming and had absolutely no nitrates in the system.

"OUCH". Last weekend my power went out for 4 hours. When the power came back on I guess the ATI Hybrid went back to factory settings and looks like I fried some of the corals. I have never run the Led's higher than 80%. They were running at 100% all week and the colours in the corals have paled out since last weekend. I just figured it out today.

Other than that I am not running any GFO for several days and my phosphorus levels have not gotten about .003ppm or 1 on the Hanna ULR checker.

Hopefully the coral colour issue was the lights.

Sorry to hear. I can't believe that such a high end fixture doesn't have a failsafe for that.

Sorry to hear about your timer issue ...

Glad to hear you've been able to remove your GFO.
If you recall from our conversation, that was the main reason I suggested adding some form of NO3. It wasn't to color up your corals, but glad that's been a positive effect.

I'm still GFO free, and haven't needed to add any NO3 since my last report.
I'll be more than doubling my fish load in a couple weeks, so hopefully I'll get some PO4 back in my tank soon.
Still sitting @ zero for both NO3 and PO4, even with heavy overfeeding of my 4 fish.
I'd like to get my readings up a bit, but my corals appear to be perfectly happy for now in the zero range.

Looking forward to your reports now that you've removed your GFO.

From what I have read it will hold the settings for a short while. But when the power goes out for a long time everything is lost even the clock settings. AS nice a unit it is it is extremely difficult to program.

Yikes! Roasting corals sucks - it's a long road to recovery. :(

I just re-started NaNO3 dosing too, but I'm adding KH2PO4 as well since I have neither measurable in my tank. Makes sure you don't bottom out PO4. :)

I am hopeful the corals will be OK. The only one I may loose is a mystic sunset monti. Not the end of the world as I am battling the early stages of monti nudibranchs Likely stress of the water changes combined with stress from the lighting combined with the nudibranchs.

I am trying to get 2ppm NO3 and .03 ppm PO4. As of yesterday I was at .003 ppm Phosphate 1/10th of where I want to be.

MY tank is sucking up the phosphate and the NO3 right now.

Where do you get the Potassium phosphate? What rate are you dosing?

I got it from a friend, pretty sure he got it from "The Plant Guy". Google it, he's Canadian. Not allowed to post a link.

I'm adding 0.02 ppm per day right now to see what happens. So far only dosed twice.

Great let me know how it goes with the phosphate. I tested mine last night and I had .02ppm phosphate. I am happy with that for now.