Carbon Dosing Questions

[Fish Fan]

Hey guys!

I've got an IM 25 gallon AIO that's relatively new, no fish at all, lightly stocked with just a handful of small frags, and for the first time ever I'm in a situation where this tank is running really, really high nitrates (75 ppm+) and very low phosphates (3 ppB phosphorus) on my Hanna Checkers. With water changes I've got the nitrates down to about 50 ppm, but they have been really high for the entire short life of this tank (started in March).

Admittedly, I'm at a loss for what's going on, I've never had sky high nitrates yet basically no phosphates. I had been feeding this tank practically nothing as I have no fish, only recently have I been giving the CUC a pinch of supplemental food here and there, and for the last few days I've been adding Reef Roids in an effort to get the phosphates up. This tank was started with about 50% totally new, dry base rock, and 50% well-cycled base rock (with some TBS live rock rubble in the filter section), and I would have thought if anything there would be high phosphates coming off the new dry rock.

Given my situation, I thought this tank would be a good candidate for carbon dosing (high nitrate, but low phosphate). About two weeks ago I installed an IM NuvoSkim protein skimmer in anticipation of carbon dosing. On Monday (day 1), I added about 3mL of a 75%/25% solution of white vinegar and 80 proof vodka. Almost immediately, the water turned cloudy and I thought, alright, that's the bacterial boom. On Tuesday (day 2) the water was still very cloudy, but I added another ~3ml of the carbon solution. On Wednesday (day 3) the water was still very cloudy, so I did not add any more carbon. Today, Thursday (day 4) the water was still could, I'd say there's been no change since day one, so I didn't not add any carbon today either.

I guess my questions are first, am I doing something wrong? Am I adding too much carbon (about 3mL/day in a 25 gallon tank)? Second, how long should it take for the water to clear up and was I wise or impatient by not dosing carbon over the last couple days? Last, is it possible that my humble IM NuvoSkim skimmer is just not up to the task of removing the bacteria in this situation?

As always, any help would be greatly appreciated! Thank you in advance!

 

[Catawba_Valley_Reef]

In my experience the nuvo skimmers aren’t very good. I liked the old aquamaxx hob and nf skimmers. I think they are now called aqua ready.

Things I’ve noticed in my reefing journey over the last 20 years. Sometimes when no3 is really high it can suppress po4 and vice versa. I’m wondering if you continued doing some larger water changes and brought down no3 even more, maybe po4 would start to increase.

With carbon dosing, it will not work unless you have enough po4 available. When I carbon dosed in the past, my no3 wouldn’t go down and then through research I figured out the po4 was too low for it to work. Once I got the po4 up it started lowering my no3…but pretty much only works on lowering no3.

In a 25 gallon tank I would rely on water changes for no3 control. I just don’t think carbon dosing is worth it in a small volume of water. It suppresses your ph, depending on vodka or vinegar ratios, it can lead to cyano. Just another variable to go wrong when a 10 or 15 gallon water change could fix so many issues.

I probably didn’t answer any of your questions but wanted to share my experience.

 

[Idech]

Have you tested with more than one kit ? Having very high nitrates with no fish and little to no feeding is strange.

 

[rishma]

When I’ve encountered cloudy water when carbon dosing, I always stop until it clears for fear of oxygen deficiency. I’d have done the same thing.

Looking at @Miami Reef dosing charts, you did dose a little more than the equivalent week 1 dosing recommendation but not a big overdose. I’m a little surprised you got a bacterial bloom.

I would absolutely raise phosphate before carbon dosing.

 

[Fish Fan]

Thank you very much for you help here!

In my experience the nuvo skimmers aren’t very good. I liked the old aquamaxx hob and nf skimmers. I think they are now called aqua ready.

I am tempted to believe this, but I purchased it because it was their updated model, and it got good reviews.

Things I’ve noticed in my reefing journey over the last 20 years. Sometimes when no3 is really high it can suppress po4 and vice versa. I’m wondering if you continued doing some larger water changes and brought down no3 even more, maybe po4 would start to increase.

I ran this tank for several months in the dark with the rocks I mentioned above, and no other livestock at all. Over the last many months, I have done many nearly 100% water changes and the nitrate always comes back (and they are not in my new mixed saltwater, I checked).

With carbon dosing, it will not work unless you have enough po4 available. When I carbon dosed in the past, my no3 wouldn’t go down and then through research I figured out the po4 was too low for it to work. Once I got the po4 up it started lowering my no3…but pretty much only works on lowering no3.

Hmmm, this I'm not following. If thew bacteria are blooming and making my water cloudy, how are they growing if there isn't enough phosphates for them? And in my research, carbon dosing affects phosphates much less than nitrates. I'm all ears if you can help me to understand this.

I probably didn’t answer any of your questions but wanted to share my experience.

Thank you again for your reply, I very much appreciate it

 

[ReefQuestCorals]

Why not let it naturally come down? I heard of this issue after cycling a new system with ammonium chloride but i did not see this issue on my most recent system.

I feel if you start trying to manage nutrients this early you can throw off the balance. For example i attempted to manage nutrients in my 3 month old system and ended up almost crashing nitrate and phosphate came real close. I could see some color loss and what growth was i was seeing slowed down. Took me about 1 month and finally got nutrients stabilized without almost daily dosing.

 

[Fish Fan]

Have you tested with more than one kit ? Having very high nitrates with no fish and little to no feeding is strange.

Preaching to the Choir!

I've used my Hanna HR nitrate checker, as well as a Red Sea kit.

I'm not ready to say that this isn't some kind of testing error, because it's so strange to me, but I've run so many tests on this tank, and they are all the same. And my Hanna reagents are all recently fresh.

Thank yo for your help here!

 

[Fish Fan]

Why not let it naturally come down? I heard of this issue after cycling a new system with ammonium chloride but i did not see this issue on my most recent system.

I feel if you start trying to manage nutrients this early you can throw off the balance. For example i attempted to manage nutrients in my 3 month old system and ended up almost crashing nitrate and phosphate came real close. I could see some color loss and what growth was i was seeing slowed down. Took me about 1 month and finally got nutrients stabilized without almost daily dosing.

I think what you mean is that tanks that are fish-less cycled using ammonium chloride often end up with very high nitrates after the initial nitrogen cycle.

Unfortunately, that's not what happened here

This tank was started using 50% dry rock, 50% well cycled rock (about 18 months running). I ran it dark for almost three months, and during that time I added a few pieces of TBS live rock in the display. I also added TBS live rock rubble in the filter section. This tank has been running since late February or early March. I've done nearly 100% water changes, and the nitrates come back.

Thank you for your help and reply!

 

[jsker]

Start small and work your way up. I used Costco vodka with a doser.

 

[ReefQuestCorals]

Why not let it naturally come down? I heard of this issue after cycling a new system with ammonium chloride but i did not see this issue on my most recent system.

I feel if you start trying to manage nutrients this early you can throw off the balance. For example i attempted to manage nutrients in my 3 month old system and ended up almost crashing nitrate and phosphate came real close. I could see some color loss and what growth was i was seeing slowed down. Took me about 1 month and finally got nutrients stabilized without almost daily dosing.

I think what you mean is that tanks that are fish-less cycled using ammonium chloride often end up with very high nitrates after the initial nitrogen cycle.

Unfortunately, that's not what happened here

This tank was started using 50% dry rock, 50% well cycled rock (about 18 months running). I ran is dark for almost three months, and during that time I added a few pieces of TBS live rock in the display. I also added TBS live rock rubble in the filter section. This tank has been running since late February or early March.

Thank you for your help and reply!

Your right sorry i was being asked questions by my new guy at work while replying got me all thrown off.

I had missed the questions at the bottom. Dang FNG messing with my concentration

 

[Fish Fan]

When I’ve encountered cloudy water when carbon dosing, I always stop until it clears for fear of oxygen deficiency. I’d have done the same thing.

Looking at @Miami Reef dosing charts, you did dose a little more than the equivalent week 1 dosing recommendation but not a big overdose. I’m a little surprised you got a bacterial bloom.

I would absolutely raise phosphate before carbon dosing.

Thank you for you're help here!

I thought it was decided that the slow ramp up to dosing carbon was largely necessary? But yes, I stopped dosing as I am still seeing cloudy water, but the good news from an O2 point of view is that I have no fish here.

I get why bacteria need phosphates, but even with my very low phosphate I'm seeing a bloom. I'm not understanding how the bacteria can grow to a point where my water is cloudy, but there's not enough phosphate for them. Again, if someone could help me out here, I'd appreciate it!

As always, thank you for your help, I appreciate it!

 

[Fish Fan]

Your right sorry i was being asked questions by my new guy at work while replying got me all thrown off.

I had missed the questions at the bottom. Dang FNG messing with my concentration

No worries! I appreciate your help here!

 

[Fish Fan]

Start small and work your way up. I used Costco vodka with a doser.

Thank you for your help here! Is this the newest chart? I think MiamiReef and RFH decided that the slow ramp up was uneccessary?

Could it be that I've just overdosed the carbon at this point? Maybe give it a few days and when is clear, maybe dose like 1mL?

I decided on a mixture of vinegar and vodka because I've read that dosing only one can lead to a "monoculture" of just one variety of bacteria. I have also read that only using vodka can potentially lead to cyano outbreaks.

I could very well be wrong about all of this, so please correct me if I'm am! I mean, I was wrong about something once back around 1984, I guess I could be wrong here too

Thank you very much for your help!

 

[rishma]

Thank you very much for you help here!

In my experience the nuvo skimmers aren’t very good. I liked the old aquamaxx hob and nf skimmers. I think they are now called aqua ready.

I am tempted to believe this, but I purchased it because it was their updated model, and it got good reviews.

Things I’ve noticed in my reefing journey over the last 20 years. Sometimes when no3 is really high it can suppress po4 and vice versa. I’m wondering if you continued doing some larger water changes and brought down no3 even more, maybe po4 would start to increase.

I ran this tank for several months in the dark with the rocks I mentioned above, and no other livestock at all. Over the last many months, I have done many nearly 100% water changes and the nitrate always comes back (and they are not in my new mixed saltwater, I checked).

With carbon dosing, it will not work unless you have enough po4 available. When I carbon dosed in the past, my no3 wouldn’t go down and then through research I figured out the po4 was too low for it to work. Once I got the po4 up it started lowering my no3…but pretty much only works on lowering no3.

Hmmm, this I'm not following. If thew bacteria are blooming and making my water cloudy, how are they growing if there isn't enough phosphates for them? And in my research, carbon dosing affects phosphates much less than nitrates. I'm all ears if you can help me to understand this.

I probably didn’t answer any of your questions but wanted to share my experience.

Thank you again for your reply, I very much appreciate it

I agree that carbon dosing has a much bigger impact on nitrates than phosphates. However, it does have some impact on phosphate and yours is so low that I fear bottoming out phosphate and all the troubles that can come with it. 3ppb is within test error if 0 ppb.

I have bottomed out phosphate with carbon dosing. It was not pretty.

 

[Fish Fan]

I agree that carbon dosing has a much bigger impact on nitrates than phosphates. However, it does have some impact on phosphate and yours is so low that I fear bottoming out phosphate and all the troubles that can come with it. 3ppb is within test error if 0 ppb.

I have bottomed out phosphate with carbon dosing. It was not pretty.

Agreed, the 3.0 ppb on the Hanna ULR Phosphorus Checker is effectively zero, and indeed I get 0.00 on my Hanna ULR Phosphate Checker that reads in ppm.

I also understand that it would be unwise to bottom out phosphates, and with that in mind, maybe I didn't think this through well enough because had things worked the way I would have hoped, I may very well have stripped away the very last of my phosphates

But that said, I'm still at a loss as to how the bacteria can grow enough to cause a multi day cloudy period, but I don't have enough phosphate in the water for carbon dosing to work. Is what I'm asking even making sense, or am I way confused here? For the phosphate to bottom out, the bacteria would have to be using it as they grow. I'm still measuring about the same for phosphate, yet the bacteria is visibly growing. I'm assuming it's bacteria as this tank has been nothing but clear since its inception, and became cloudy shortly after adding the first carbon dose.

If I could manage all this with water changes, I would, but even without fish this is just going to get worse as I get more and larger corals, and will be feeding them more.

Thank you for your help!

 

[Fish Fan]

I appreciate everyone's help and input here!

I'm going to run another round of tests tomorrow and hopefully do a water change, especially if it's still cloudy.

Thanks again guys, I appreciate the help!

 

[jsker]

Thank you for your help here! Is this the newest chart? I think MiamiReef and RFH decided that the slow ramp up was uneccessary?

Could it be that I've just overdosed the carbon at this point? Maybe give it a few days and when is clear, maybe dose like 1mL?

I decided on a mixture of vinegar and vodka because I've read that dosing only one can lead to a "monoculture" of just one variety of bacteria. I have also read that only using vodka can potentially lead to cyano outbreaks.

I could very well be wrong about all of this, so please correct me if I'm am! I mean, I was wrong about something once back around 1984, I guess I could be wrong here too

Thank you very much for your help!

This is an older chart, I did the math and came up with my own dosing schedule for my old tank of 82 gallons of volume.

I over dosed once, I could smell the vodka when I hit the room. I did not have a bloom, but I think the fish were feeling no pain

The mixture is a Randy question. Once a start dosing vodka my long standing cyano issues went away. I will dose vodka in my new system when I set the system up.

Without attempting, one will never discover the answer. A question not posed is the incorrect one.

I my experence nitrates are caused by waist. Sense you have no fish and a new system your Po4 and No3 are going have to settle in.

Your welcome, have a great one.

 

[Fish Fan]

This is an older chart, I did the math and came up with my own dosing schedule for my old tank of 82 gallons of volume.
I over dosed once, I could smell the vodka when I hit the room. I did not have a bloom, but I think the fish were feeling no pain

Lol! That cracked me up!

Do you think if I took your numbers at 82 gallons and by ratio dosed the same for my 25 gallon (probably closer to 20 gallon water volume) I'd be in good shape?

Again, I must have read something wrong about the ramp-up phase. Maybe I should have started much lower.

I agree with RHF in that reply tho nitrates are caused by waste, and I have no explanation in this tank, except that some of the rocks had been in another aquarium, and may have built up some organics. The new, dry rock may have also had some organics (though nearly no phosphates??). Or the TBS rocks honestly did have some life to them.

A very dimly lit light bulb just went off for me, maybe - during the initial dark period where again I had some TBS rock and rocks that were well seasoned by TBS rock, this tank grew pineapple sponges everywhere. I mean, they were all over the rocks in the display section, and I assume they were and still are in the dark filter section with the TBS rock rubble pieces. Could the die off of these sponges be causing what I'm seeing here? This just popped into my head, am I on to something here?

 

[rishma]

It probably doesn’t take much phosphate to enable a bloom. With test error, etc I wouldn’t over think it. I’d just dose phosphate to a stable level before working to bring down nitrate.

I don’t worry too much about nitrate, honestly. The phosphate is the more immediate concern in my opinion. It may take more effort than expected to raise it to a stable level.

 

[Fish Fan]

It probably doesn’t take much phosphate to enable a bloom. With test error, etc I wouldn’t over think it. I’d just dose phosphate to a stable level before working to bring down nitrate.

Friend, what am I missing here? I'm genuinely asking

How could the phosphate be so low that I need more in the tank, yet I'm seeing a visible bacteria bloom, which to me suggests that the bacteria are growing and growing well? To me, this seems much more like I need a better skimmer, and without a better skimmer carbon dosing isn't a good fit for this tank.

What would happen if I did add more phosphate (which I'm currently trying to do by adding Reef Roids (all I have on hand))? Wouldn't the bacteria grow even faster, causing cloudier water, and while that growth might use up much of my nitrates and some of my very limited phosphates, it's basically meaningless if I don't have a skimmer capable of pulling the bacteria out?

Again, if I'm completely misunderstanding this carbon dosing process, by all means someone please let me know what I'm missing

Thank you very much again for your help, I really do appreciate it, I'm just kind of slow sometimes