pH drop and carbon dosing

[Stephers]

I have a NPS tank with lots of gorgonians and they seem very sensitive to lower pH. Their polyps don't come out. I dose vinegar on this tank to control nitrates, and turning the carbon dosing on and off, there seems to be a direct correlation to the polyps not coming out when vinegar is dosed and then being very happy and open when the vinegar dosing if off after a couple days. The softies and LPS seem unaffected. Seems to be only the gorgonians. The only thing that makes sense to me is the pH being lowered and I've seen some reports by other that they've observed similar with low pH and gorgonians.

This puts me in a bind as the food input is really high and it's only 7 gallons. I use almost only live foods and do a 30% water change weekly, but it's still a challenge.
I thought about changing to vodka, but I've read from Randy that while the pH drop with vinegar happens at the moment it's dosed, vodka ends up reducing the pH to the same extent except over time.

I counteract the vinegar pH drop on my main tank by using sodium hydroxide as an alk additive, but the NPS tank consumes very little alk due to most of the inhabitants not having a stony structure. Are there any viable options to keep the pH up while still carbon dosing?

 

[Euphyllia97]

I’m wondering if adding an airstone/more oxygen would be beneficial to your problem

 

[56longroof]

If your tank is only 7 gallons I would just control nutrients with larger water changes.

 

[Fish Fan]

If your tank is only 7 gallons I would just control nutrients with larger water changes.

^This 100%. If a 30% water change isn't doing it, change a greater percentage of water. If you don't already, get a 5 gallon food grade bucket and lid from your local Mega-Lo-Mart, an inexpensive heater and circ pump and mix and heat your water in advance. Subtracting for your rocks and sand, 5 gallons would allow you to change out close to 100% of your 7 gallon, if needed.

I don't believe carbon dosing is going to help you here. The dirty secret they don't tell you about carbon dosing is that it really requires a good protein skimmer, which I assume you don't have on a 7 gallon, to remove the bacteria you've fed with the carbon. That's what actually removes the nutrients, without a skimmer, you're just growning bacteria. Will the bacteria sequester some nutrients and can your filter feeding organisms benefit from the bacteria in the water? For sure. But I would skip the hassle of carbon dosing on a 7 gallon, and just change out more water

Good luck!

 

[bubbgee]

^This 100%. If a 30% water change isn't doing it, change a greater percentage of water. If you don't already, get a 5 gallon food grade bucket and lid from your local Mega-Lo-Mart, an inexpensive heater and circ pump and mix and heat your water in advance. Subtracting for your rocks and sand, 5 gallons would allow you to change out close to 100% of your 7 gallon, if needed.

I don't believe carbon dosing is going to help you here. The dirty secret they don't tell you about carbon dosing is that it really requires a good protein skimmer, which I assume you don't have on a 7 gallon, to remove the bacteria you've fed with the carbon. That's what actually removes the nutrients, without a skimmer, you're just growning bacteria. Will the bacteria sequester some nutrients and can your filter feeding organisms benefit from the bacteria in the water? For sure. But I would skip the hassle of carbon dosing on a 7 gallon, and just change out more water

Good luck!

This!

I was wondering what was wrong with my nano when I was dosing nopox and killing my corals. A protein skimmer shouldn't be optional when doing vodka or carbon dosing.

 

[Stephers]

If your tank is only 7 gallons I would just control nutrients with larger water changes.

^This 100%. If a 30% water change isn't doing it, change a greater percentage of water. If you don't already, get a 5 gallon food grade bucket and lid from your local Mega-Lo-Mart, an inexpensive heater and circ pump and mix and heat your water in advance. Subtracting for your rocks and sand, 5 gallons would allow you to change out close to 100% of your 7 gallon, if needed.

I don't believe carbon dosing is going to help you here. The dirty secret they don't tell you about carbon dosing is that it really requires a good protein skimmer, which I assume you don't have on a 7 gallon, to remove the bacteria you've fed with the carbon. That's what actually removes the nutrients, without a skimmer, you're just growning bacteria. Will the bacteria sequester some nutrients and can your filter feeding organisms benefit from the bacteria in the water? For sure. But I would skip the hassle of carbon dosing on a 7 gallon, and just change out more water

Good luck!

This!

I was wondering what was wrong with my nano when I was dosing nopox and killing my corals. A protein skimmer shouldn't be optional when doing vodka or carbon dosing.

I figured one of the benefits of the carbon dosing was actually the corals and sponges and tunicates consuming some of the bacteria being produced since they are NPS organisms. It will be tricky to do a larger water change mostly because the tunicates and sponges are not ever supposed to be exposed to air, and they're about halfway up the tank and cannot be moved at this point.

I’m wondering if adding an airstone/more oxygen would be beneficial to your problem

Thanks. I guess it's something I can try. I do have one powerhead positioned close to the top and is stirring that pretty well, but maybe an airstone in the overflow would help.

 

[56longroof]

I figured one of the benefits of the carbon dosing was actually the corals and sponges and tunicates consuming some of the bacteria being produced since they are NPS organisms. It will be tricky to do a larger water change mostly because the tunicates and sponges are not ever supposed to be exposed to air, and they're about halfway up the tank and cannot be moved at this point.



Thanks. I guess it's something I can try. I do have one powerhead positioned close to the top and is stirring that pretty well, but maybe an airstone in the overflow would help.

You can do several smaller water changes or two 30% a week until nitrates are where you want them. I dose vinegar and still have trouble with sponges. I think phyto would be better. Im currently setting up a large algea reactor to move away from carbon dosing. The excess bacteria is just becoming a nuisance in the sump. Slime everywhere.

 

[Randy Holmes-Farley]

What time of day do you dose the vinegar?

 

[Stephers]

What time of day do you dose the vinegar?

I was doing the doses only during the photoperiod. I then switched to smaller doses every hour 24/7 and they seemed to hate that more. This tank gets virtually no light. It's on the lowest setting possible on the fixture and the par reader reads as 10 at the top of the tank.

 

[Randy Holmes-Farley]

Are you measuring pH at all?