New Avast Marine Calcium Reactor

[Crashjack]

Is there a reason you choose not to use the ph controller to maintain your desired ph? I wouldn't change pressure on regulator, it will definitely change the operation and make things more complex. With this design we fix all the variables, input water flow, input water pressure, outlet water pressure and flow and assume co2 pressure is fixed, this leaves only ph to worry about. The benefit to this is you only have to change 1 variable toi increase/decrease output alkalinity.

That's a good question, and I started that way but then changed for a few reasons:

1. Doing my way, pH readings become just a reference sort of like a bubble counter. When one uses pH readings to manage the reactor, if the pH probe fails or gives bad readings you run the risk of fluctuating alkalinity until you discover, and you pretty much have to shut the reactor down until fixed. My way, I can keep the reactor going without the pH probe working properly or at all until I can fix the problem or replace the probe.
2. When you manage with pH setpoints, you have to run CO2 a little high to keep hitting the low setpoint. Therefore if there is an issue to where your low setpoint doesn't shut down your CO2 dispenser (bad pH readings or probe failure, programming error or accidently entering the wrong setpoint value, or even a controller hiccup), you would likely create a situation where you are overdosing Ca/alk. When you setup to where you allow your CO2 dispenser to run continuously, you can use your low CO2 setpoint merely as a failsafe. In my opinion, this is much safer.
3. Managing with CO2 set points would require one of my relays and my Carbondoser to turn on/off multiple times every hour. I just feel like there is less wear and tear on my relays and my Carbondoser when they aren't turning on and off all of the time.

 

[AVAST Marine]

Sounds like you have a pretty good handle on everything and I agree with most of what you are saying here. I would just caution against changing the pressure of the regulator with our reactor, and use your management system applied to a single variable (bubble count) to control. I would also encourage everyone to regularly test effluent alkalinity since this is the easiest way to spot an issue before it becomes a problem (like a failing probe). I am pretty sure the carbon doser uses a NC solenoid, so when it is on is the only time you would experience wear, not from a on/off cycle, even then I know they use the best components available (why we recommend them) so I personally wouldn't sweat wear and tear of that.

I really appreciate you taking the time to detail out your method, we will keep this in mind next time we update the Seabones manual so we can include a few more detail points on alternate operation methods

 

[Crashjack]

Sounds like you have a pretty good handle on everything and I agree with most of what you are saying here. I would just caution against changing the pressure of the regulator with our reactor, and use your management system applied to a single variable (bubble count) to control. I would also encourage everyone to regularly test effluent alkalinity since this is the easiest way to spot an issue before it becomes a problem (like a failing probe). I am pretty sure the carbon doser uses a NC solenoid, so when it is on is the only time you would experience wear, not from a on/off cycle, even then I know they use the best components available (why we recommend them) so I personally wouldn't sweat wear and tear of that.

I really appreciate you taking the time to detail out your method, we will keep this in mind next time we update the Seabones manual so we can include a few more detail points on alternate operation methods

I have my Carbondoser set to dispense CO2 every 3+ seconds. This allows me to make small changes to low-side pressure without creating a large increase/decrease in reactor pH. My adjustments are always .5 PSI or less (according to the low-side gauge), which typically results in average reactor pH increasing/decreasing .05 pH or less. Again, I say average because reactor pH tends to increase during the daylight hours and decrease during night/early morning hours. I also test alkalinity 2x per week, and the small adjustments haven’t made my alkalinity shoot way up or way down.

I don't actually use a bubble counter. I let my reactor pH be my reference instead of watching a bubble counter. With the Carbondoser, the dial sets the “bubble count”, and the low side pressure sets the “bubble size”. I rarely adjust the dial because it would be hard to make precise adjustments. However, it isn't that difficult to make fairly precise adjustments with low side pressure changes--at least when you have the dial set to release CO2 every few seconds. Hence, my single variable is low-side pressure = bubble size. Another nice thing about using reactor pH as a reference is that an unexpected drop in reactor pH typically means the flow restrictor is at least partially clogged (a big pH drop would likely mean the flow restrictor is totally clogged). Just curious, why do you recommend against adjusting low-side pressure?

 

[AVAST Marine]

Yes the carbon doser bubble count is still a bubble counter even though it is not the traditional type. Changing pressure = changing bubble size but it still affects the internal pressure of the reactor. Keeping pressure constant and adjusting frequency of the count is the recommended setup mainly because it is easier to implement, monitor and not everyone uses a Carbondoser

 

[Dennis Cartier]

I am curious if you have to vent this style of reactor? Meaning, replacing the CO2 gas that is inside the reactor with fresh CO2.

The reason I am curious, is that I run an ACR, and with that style of reactor, you have to vent it periodically or the effluent strength will eventually decline as non-CO2 gasses build up. I have mine set to vent itself once a week, and that keeps my effluent at 73 dKh (64.4 of that added by CaRx). Both styles of reactor use a pocket of CO2.

So is anyone finding they need to vent the Avast CaRx?

Dennis

 

[135zman]

I have never found the need to vent since it is not designed as an airtight system. It is about as simple to operate as any piece of reef equipment that I’ve tried over many years of reefkeeping. I use it as a supplement to my regular All for Reef dosing.

 

[AVAST Marine]

I am curious if you have to vent this style of reactor? Meaning, replacing the CO2 gas that is inside the reactor with fresh CO2.

The reason I am curious, is that I run an ACR, and with that style of reactor, you have to vent it periodically or the effluent strength will eventually decline as non-CO2 gasses build up. I have mine set to vent itself once a week, and that keeps my effluent at 73 dKh (64.4 of that added by CaRx). Both styles of reactor use a pocket of CO2.

So is anyone finding they need to vent the Avast CaRx?

Dennis

The Seabones was designed to self vent any excess gas through it's effluent path if needed.