Carbon dosing and/or macroalgae right for me?

[Barnacle1]

Hello,

I have a 40 gallon mixed reef. I am using rowaphos in a media bag to keep the phosphates down, and it seems that the live rock is doing its job as far as denitrification.

I only have 2 small fish and plan on ending up with 4-5X the current fish bioload.

Would it make sense to forgo a macroalgae refugium and jump right into to carbon dosing? I do not own a refugium light, but I do own a doser, so the cost would only be the bottle of vinegar or NO3-PO4-x. Not that the fuge light would be prohibitively expensive.

At some point should I consider discontinuing use of the GFO?

Thanks,
Anthony

 

[glb]

Hello,

I have a 40 gallon mixed reef. I am using rowaphos in a media bag to keep the phosphates down, and it seems that the live rock is doing its job as far as denitrification.

I only have 2 small fish and plan on ending up with 4-5X the current fish bioload.

Would it make sense to forgo a macroalgae refugium and jump right into to carbon dosing? I do not own a refugium light, but I do own a doser, so the cost would only be the bottle of vinegar or NO3-PO4-x. Not that the fuge light would be prohibitively expensive.

At some point should I consider discontinuing use of the GFO?

Thanks,
Anthony

I switched from gfo to Nopox and have been very happy. I have a 40g and Nopox keeps nitrates at 5-10 and phosphates at about 0.03. You don’t really need to use the doser since you can dose all at once. But dosers are cool, lol. I may add an algae reactor to help with ph so we’ll see if I need the Nopox then. The gfo was a pain IMO.

 

[Dennis Cartier]

If you are like most reefer's, the GFO will eventually become a nuisance. Whether it is due to cost, or maintenance or the care required to not strip all the PO4 from your tank. Over the past couple of years I have endeavoured to try all the various nutrient control strategies on my frag tank while going through a long DT build process.

I have experimented with the following techniques:

• DIY Nopox
• Sulfur denitrfication
• Bio pellets
• Iron dosing
• Fuge with chaeto

DIY Nopox

This worked pretty well. It was a bit of a challenge to setup on an auto doser as the amount required kept changing, most likely caused by bound phosphate being released from my rock/sand. I also had to dose nitrate using this method, but that would have probably eventually resolved once the PO4 and NO3 got into balance.

Sulfur denitrification

Rather than use an off the shelf reactor, I constructed what I called sulfur sticks. Basically pond sized Siporax stacked end to end, with some needle point canvas cut into a long strip and inserted down the middle to hold them all together. Then the middle was filled with sulfur preens and had a bit of canvas tucked into each end to keep them there. A largish reactor was filled with these and water was flowed through them. I used them for about a year and a half. When I took them offline, about 75% of the sulfur had been consumed. The tank looked great while I was using this method. I did have issues keeping alk in balance with calcium though due to the sulfur denitrification using up alk during the process. I also had challenges keeping phosphate down, so I ended up using LaCl to assist with this. The reason I discontinued it was its inability to deal with PO4 and the out of balance Alk consumption.

Bio Pellets

I tried the All-In-One bio pellets in a couple of different reactors. They do work, but I experienced too low Po4 with the first bag that I purchased when they first hit the market. When I ran out of those and purchased a new bag, I noticed the colour had changed dramatically (of the pellets). The older bag was dark brown, the new pellets were light tan. I suspect the manufacturer reduced the amount of iron they mixed into the newer pellets. What I found was that this brand left a brown/tan mulm all over the sump. Many reefers report the same thing. Controllability is a challenge with bio pellets in general (especially with the first versions of these and PO4). My level of husbandry is just not up to the level required by these to keep them working effectively.

Iron Dosing

While using the sulfur reactor, I started looking for different means of lowering just PO4. I found that LaCl worked, but I was not comfortable with the risks to my fish that it posed. Glenn from the DSR method uses a liquid iron supplement that he devised. I found that the DIY Iron Citrate recipe that RHF posted several years ago, could indeed lower PO4 when dosed in sufficient amounts. Like LaCl dosing, care must be taken as it can negatively impact livestock. Unlike LaCal, we know what effect Iron has on a tank if residual amounts do not get removed. This is my go to method of phosphate reduction at the moment should PO4 need to be reduced without affecting NO3.

Fuge with Chaeto

After seeing the BRS video on different fuge lights, I decided to setup an external fuge with a Kessil H380. I used a 20 gallon brute barrel with a ball of chaeto rotating over an upward facing feed pipe. Wow, the ability of the H380 to grow macro algae and in the process lower nutrients, is quite remarkable. Now I have the opposite issue. Too low of nutrients (at least too low of NO3). All my frags stopped growing as the NO3 crept lower and lower. When it got to 0.2 ppm, I decided to act and lower the lighting period of the fuge while also cutting the ball back to 1/4 the size. This allowed my No3 to go up to 1 ppm and my corals started to colour back up and grow again. My PO4 settles at 0.08 ppm using this method, which is higher than a lot of people suggest, but I have found my tank seems to do best at this level. I have to dose extra iron and Iodine and keep an eye on Potassium when using this method. I plan on experimenting with modulating the fuge light period once the Reef Bot becomes available using a PID loop to affect the H380 duty cycle based on measured NO3 levels.

What I have found, is that there are lots of ways to do nutrient exports these days. Most of which are too effective. That being said, your tank will adapt to whatever method and nutrient level you end up targeting, given enough time. It is really up to the you the reefer to decide what works best and how much effort you are willing to expend to keep up with a particular method to allow your tank to become balanced using it.

Dennis

 

[Randy Holmes-Farley]

I used both macroalgae and carbon dosing at the same time. Organic Carbon dosing will export more nitrate than phosphate, and may leave residual phosphate. Macroalgae wont generally do that.

I like carbon dosing (vinegar) because it (acetate in vinegar) feeds corals and other organisms directly and the bacteria are also good for other organisms.

 

[Barnacle1]

If you are like most reefer's, the GFO will eventually become a nuisance. Whether it is due to cost, or maintenance or the care required to not strip all the PO4 from your tank. Over the past couple of years I have endeavoured to try all the various nutrient control strategies on my frag tank while going through a long DT build process.

I have experimented with the following techniques:

• DIY Nopox
• Sulfur denitrfication
• Bio pellets
• Iron dosing
• Fuge with chaeto

DIY Nopox

This worked pretty well. It was a bit of a challenge to setup on an auto doser as the amount required kept changing, most likely caused by bound phosphate being released from my rock/sand. I also had to dose nitrate using this method, but that would have probably eventually resolved once the PO4 and NO3 got into balance.

Sulfur denitrification

Rather than use an off the shelf reactor, I constructed what I called sulfur sticks. Basically pond sized Siporax stacked end to end, with some needle point canvas cut into a long strip and inserted down the middle to hold them all together. Then the middle was filled with sulfur preens and had a bit of canvas tucked into each end to keep them there. A largish reactor was filled with these and water was flowed through them. I used them for about a year and a half. When I took them offline, about 75% of the sulfur had been consumed. The tank looked great while I was using this method. I did have issues keeping alk in balance with calcium though due to the sulfur denitrification using up alk during the process. I also had challenges keeping phosphate down, so I ended up using LaCl to assist with this. The reason I discontinued it was its inability to deal with PO4 and the out of balance Alk consumption.

Bio Pellets

I tried the All-In-One bio pellets in a couple of different reactors. They do work, but I experienced too low Po4 with the first bag that I purchased when they first hit the market. When I ran out of those and purchased a new bag, I noticed the colour had changed dramatically (of the pellets). The older bag was dark brown, the new pellets were light tan. I suspect the manufacturer reduced the amount of iron they mixed into the newer pellets. What I found was that this brand left a brown/tan mulm all over the sump. Many reefers report the same thing. Controllability is a challenge with bio pellets in general (especially with the first versions of these and PO4). My level of husbandry is just not up to the level required by these to keep them working effectively.

Iron Dosing

While using the sulfur reactor, I started looking for different means of lowering just PO4. I found that LaCl worked, but I was not comfortable with the risks to my fish that it posed. Glenn from the DSR method uses a liquid iron supplement that he devised. I found that the DIY Iron Citrate recipe that RHF posted several years ago, could indeed lower PO4 when dosed in sufficient amounts. Like LaCl dosing, care must be taken as it can negatively impact livestock. Unlike LaCal, we know what effect Iron has on a tank if residual amounts do not get removed. This is my go to method of phosphate reduction at the moment should PO4 need to be reduced without affecting NO3.

Fuge with Chaeto

After seeing the BRS video on different fuge lights, I decided to setup an external fuge with a Kessil H380. I used a 20 gallon brute barrel with a ball of chaeto rotating over an upward facing feed pipe. Wow, the ability of the H380 to grow macro algae and in the process lower nutrients, is quite remarkable. Now I have the opposite issue. Too low of nutrients (at least too low of NO3). All my frags stopped growing as the NO3 crept lower and lower. When it got to 0.2 ppm, I decided to act and lower the lighting period of the fuge while also cutting the ball back to 1/4 the size. This allowed my No3 to go up to 1 ppm and my corals started to colour back up and grow again. My PO4 settles at 0.08 ppm using this method, which is higher than a lot of people suggest, but I have found my tank seems to do best at this level. I have to dose extra iron and Iodine and keep an eye on Potassium when using this method. I plan on experimenting with modulating the fuge light period once the Reef Bot becomes available using a PID loop to affect the H380 duty cycle based on measured NO3 levels.

What I have found, is that there are lots of ways to do nutrient exports these days. Most of which are too effective. That being said, your tank will adapt to whatever method and nutrient level you end up targeting, given enough time. It is really up to the you the reefer to decide what works best and how much effort you are willing to expend to keep up with a particular method to allow your tank to become balanced using it.

Dennis

Thanks for the reply. I was under the impression LaCl was totally safe. Do you know where I can find some more info about the risks?

 

[Barnacle1]

I used both macroalgae and carbon dosing at the same time. Organic Carbon dosing will export more nitrate than phosphate, and may leave residual phosphate. Macroalgae wont generally do that.

I like carbon dosing (vinegar) because it (acetate in vinegar) feeds corals and other organisms directly and the bacteria are also good for other organisms.

I was worried that, if many systems running organic carbon eventually become nitrate limited, macroalgae could exacerbate that problem. But it sounds like it’s the other way around. I.e. the bacteria outcompeting the macroalgae for nitrate.

Is that correct?


Looking at the MSDS of Red Sea No3-po4-X, it has acetic acid, ethanol, and methanol.

Is it safe to assume the methanol is to denature the product and ethanol>acetic acid to make the bottle smaller?

Could there be more ingredients in there or is it just water?

I think I’ll start with macroalgae then dose vinegar if needed.

Thanks for the help.

 

[Dennis Cartier]

I was worried that, if many systems running organic carbon eventually become nitrate limited, macroalgae could exacerbate that problem. But it sounds like it’s the other way around. I.e. the bacteria outcompeting the macroalgae for nitrate.

Is that correct?


Looking at the MSDS of Red Sea No3-po4-X, it has acetic acid, ethanol, and methanol.

Is it safe to assume the methanol is to denature the product and ethanol>acetic acid to make the bottle smaller?

Could there be more ingredients in there or is it just water?

I think I’ll start with macroalgae then dose vinegar if needed.

Thanks for the help.

The components of Nopox have been analyzed. Here is a thread that has a link to the NMR results along with the recipe to make your own. https://www.reef2reef.com/threads/nopox-recipe.322503/#post-3994226

You are correct, the methanol is likely used as a denaturing agent in their source ethanol to make it undrinkable.

Bacteria will out compete macro's due to the speed at which they can reproduce.

Dennis

 

[Dennis Cartier]

Thanks for the reply. I was under the impression LaCl was totally safe. Do you know where I can find some more info about the risks?

The risks are in dosing it too fast or too much of it. Some fish seem to be particularly sensitive to the particulate that is formed, and if the particulate is not captured and removed, then it can cause breathing issues for sensitive animals (especially tangs).

Lots of threads about LaCl here https://www.reef2reef.com/search/3897923/?q=LaCl&o=relevance

Dennis

 

[Barnacle1]

The risks are in dosing it too fast or too much of it. Some fish seem to be particularly sensitive to the particulate that is formed, and if the particulate is not captured and removed, then it can cause breathing issues for sensitive animals (especially tangs).

Lots of threads about LaCl here https://www.reef2reef.com/search/3897923/?q=LaCl&o=relevance

Dennis

Thanks for the info and the links.

 

[Randy Holmes-Farley]

Thanks for the reply. I was under the impression LaCl was totally safe. Do you know where I can find some more info about the risks?

Some people report adverse reactions in tangs. Whether that is coincidence or not, or a methodology issue, isn't clear.

 

[Randy Holmes-Farley]

Looking at the MSDS of Red Sea No3-po4-X, it has acetic acid, ethanol, and methanol.

Is it safe to assume the methanol is to denature the product and ethanol>acetic acid to make the bottle smaller?

Could there be more ingredients in there or is it just water?

I think I’ll start with macroalgae then dose vinegar if needed.

Thanks for the help.

FWIW, that is not the list of components. It is a safety warning. There are other ingredients (e.g., isopropanol). The two main components certainly are acetic acid (e.g., vinegar) and ethanol (e.g., vodka).

 

[Randy Holmes-Farley]

I was worried that, if many systems running organic carbon eventually become nitrate limited, macroalgae could exacerbate that problem. But it sounds like it’s the other way around. I.e. the bacteria outcompeting the macroalgae for nitrate.

Is that correct?
]

If you dose too much organic carbon, nitrate may can become low enough to limit macroalgae growth. But macroalgae actually prefers ammonia, and I'm not sure in the real world of reef tanks, how much macroalgae uses ammonia and how much it uses nitrate. That said, aerobic bacterial growth on organic carbon can also use ammonia as it's N source.

I used both macroalgae and vinegar, and didn't ever drive nutrients too low, but it can be a risk.