I understand that the Carbon Doser works very well for many in the hobby. I personally have never owned or used one. I open this topic as a form of sharing my experience and hoping to learn from the community.
I joined the R2R forum recently for 2 reasons:
1. I have always wanted a SW reef tank and want to learn from your experience before pulling the trigger.
2. As a hobby, I build custom CO2 systems and looking to learn on application to Reef systems.
Reading about the need for precise control of CO2 flow into CR got me thinking about how the Carbon Doser handles supply pressure effect and the potential impact on bubble rate.
Referred to as ‘End of Tank Dump’ (EOTD). EOTD is our hobby’s description of the technical term ‘supply pressure effect. Here is math as it relates to CO2 as PSI can increase/decrease due to temp changes on tank as well as CO2 tank drainage as it empties. Source:
https://northerncal.swagelok.com/bl...o-stage-regulator-s-effect-on-supply-pressure
In a typical (high purity Swagelok) single stage regulator the supply pressure effect may be about 1%, so a 2000 psig decrease in inlet pressure would result in a 20 psig (1% of 2000 psig) increase in outlet pressure.
In a typical two stage regulator, the supply pressure effect is approximately .01%. The 2000 psig decrease in inlet pressure to the first stage regulator would result in a 20 psig (1% of 2000 psig) increase in outlet pressure. That increase would be a 20 psig increase to the inlet of the second stage pressure regulator resulting in a 0.2 psig (1% of 20 psig or .01% of 2000 psig) decrease in outlet pressure.
Translating this information over to real world use of CO2: At 70 degrees F, CO2 tank pressure is 853 psi. A drop in temp to 60 degrees F would drop tank pressure to 747 PSI. The 106 psi drop would translate to 1.06 psi drop from a single stage regulator or a .0106 psi drop from a 2 Stage regulator.
This same math applies as a tank empties if not monitored and replaced as pressure effect is realized.
The Carbon Doser is designed using a simple, brass single stage regulator. Based on looks of the regulator, It appears to be manufactured by Cornelius and is often sold to the beverage industry.
https://fhsteinbart.com/product/double-gauge-regulator-co2-0-60-p-s-i/
I cannot locate the regulator specs on supply pressure effect, but can only assume it would be equal to or greater than the effect of a Swagelok Stainless single stage regulator with a retail price over $600.
As the Carbon Doser controls flow of bubbles using a high quality solenoid opening and closing in fractions of time, I assume the supply pressure increases &/or decreases due to tank pressure or temp changes must affect CO2 precision.
My questions to the community:
Have you experienced effects of supply pressure effect with a 1 Stage Reg or is it negligible?
Does an Apex or alternate source of CO2/PH control offset this in some way.
I don’t pretend to understand all systems and controls in this community, so any and all information is appreciated.
I joined the R2R forum recently for 2 reasons:
1. I have always wanted a SW reef tank and want to learn from your experience before pulling the trigger.
2. As a hobby, I build custom CO2 systems and looking to learn on application to Reef systems.
Reading about the need for precise control of CO2 flow into CR got me thinking about how the Carbon Doser handles supply pressure effect and the potential impact on bubble rate.
Referred to as ‘End of Tank Dump’ (EOTD). EOTD is our hobby’s description of the technical term ‘supply pressure effect. Here is math as it relates to CO2 as PSI can increase/decrease due to temp changes on tank as well as CO2 tank drainage as it empties. Source:
https://northerncal.swagelok.com/bl...o-stage-regulator-s-effect-on-supply-pressure
In a typical (high purity Swagelok) single stage regulator the supply pressure effect may be about 1%, so a 2000 psig decrease in inlet pressure would result in a 20 psig (1% of 2000 psig) increase in outlet pressure.
In a typical two stage regulator, the supply pressure effect is approximately .01%. The 2000 psig decrease in inlet pressure to the first stage regulator would result in a 20 psig (1% of 2000 psig) increase in outlet pressure. That increase would be a 20 psig increase to the inlet of the second stage pressure regulator resulting in a 0.2 psig (1% of 20 psig or .01% of 2000 psig) decrease in outlet pressure.
Translating this information over to real world use of CO2: At 70 degrees F, CO2 tank pressure is 853 psi. A drop in temp to 60 degrees F would drop tank pressure to 747 PSI. The 106 psi drop would translate to 1.06 psi drop from a single stage regulator or a .0106 psi drop from a 2 Stage regulator.
This same math applies as a tank empties if not monitored and replaced as pressure effect is realized.
The Carbon Doser is designed using a simple, brass single stage regulator. Based on looks of the regulator, It appears to be manufactured by Cornelius and is often sold to the beverage industry.
https://fhsteinbart.com/product/double-gauge-regulator-co2-0-60-p-s-i/
I cannot locate the regulator specs on supply pressure effect, but can only assume it would be equal to or greater than the effect of a Swagelok Stainless single stage regulator with a retail price over $600.
As the Carbon Doser controls flow of bubbles using a high quality solenoid opening and closing in fractions of time, I assume the supply pressure increases &/or decreases due to tank pressure or temp changes must affect CO2 precision.
My questions to the community:
Have you experienced effects of supply pressure effect with a 1 Stage Reg or is it negligible?
Does an Apex or alternate source of CO2/PH control offset this in some way.
I don’t pretend to understand all systems and controls in this community, so any and all information is appreciated.