scolson
Member
I've decided to try to keep the pH in my tank between 8.2 and 8.3 using a Kalk reactor and a Dynamic Dosing Schedule on one of my Hydros controllers. This is how I've gone about it.
Background:
Goals:
Strategy:
How To:
First thing is the dosing pump. The last time I calibrated it, I was getting 38ml/minute. Because the Hydros has a limit of 500ml/day on a dosing schedule and I know I may want to dose more than that, I'm lying to the controller and telling it that the pump only does 1/20th that amount (1.9 ml/min). That setup looks like this. Since I am gaming the flow rate, I include the multiplication factori n the pump name "(20X)".
The next part of the setup is the safety shutoffs for pH, Alkalinity, and return pumps. To do this I setup 3 generic outputs. DT dKH high is set to turn on if alkalinity goes above 9.7 and it will stay on until alkalinity drops below 9.6.
DT pH High is set to turn on if my main pH probe goes above 8.4 or my Alkatronic pH goes above 8.5 (it typically runs 0.1 higher at the moment). It will stay on until both pH measurements are below their low point settings (8.3 and 8.4.)
The final safety is DT RP Status which is on as long as both of my return pumps are running. I use this for many things like deciding if the skimmer needs to shut down, but I also don't want to dose kalk if the return pumps are not running normally. That configuration looks like this
To make a decision based on all three of these safety inputs, I created a combiner named DT Kalk Ctrl that will show as On if the return pump status is on and both the DT dKH High and DT pH High outputs are off (note the Inverse Input setting for those to items.)
Finally, I setup a Dynamic Dosing schedule that will dose at a rate of 7 litters/day when pH is at or below 8.1 and at 1 litter/day when pH is at or above 8.3. Remember that the actual amount dosed is 20X greater than what is shown in the configuration because I lied to the controller about the speed of the pump.
Finally, I use the Depends On field on the dosing schedule to disable the schedule, and thereby turn off dosing, when the DT Kalk Ctrl combiner control goes off. A couple of other things to note here, since my Alkatronic only checks alkalinity at the top of the hour, I wanted to skew when I dosed the Kalk, Since I'm dosing 48 times a day, or every 30 minutes, I have the dosing schedule setup to start at 15 minutes after midnight so my dosing happens at 15 and 45 minutes after the hour.
A couple of things not documented here are the AFR dosing because I've not actually set that up yet. Also, the kalk stirrer mixing motor. I recently hacked my Avast kalk stirrer to use a magnetic mixer because that slow grinding noise of it's 24/7 motor was driving my nuts. At the moment I am using a simple schedule to run the magnetic stirrer for 45 seconds every 30 minutes at 20 and 40 minutes after the hour. This keeps everything mixed up but allows the slurry to settle enough before the dosing starts.
I haven't experimented with the built in Kalk Stirrer setup in Hydros but I don't think you can use it with a dynamic dosing setup.
So, all-in, this is a lot of setup, and I don't really know if it is worth it. Part of my enjoyment of the hobby is doing this kind of stuff, and I know that is not true of everyone. However, I hope you find this useful. I'm happy to answer any questions you might have and I'd welcome any feedback on what could make this better.
Thanks, Scott
Background:
- My tank is 235 gallons and seems to evaporate about 1.5 gallons a day. The tank has not been up for long, so I don't know if that number will change seasonally or not but for the sake of this discussion let's assume that the maximum amount of saturated Kalk I can regularly dose is 6 liters a day.
- From an equipment standpoint, I have an 8-gallon ATO reservoir in my stand. A DIY 40/ml per minute dosing pump connected to a Hydros driver port that pushes RO water into a Kalk stirrer which then overflows saturated kalk to the sump. I also have a Hydros ATO pump that keeps my sump pump chamber at a consistent level.
- I have a pH probe in the sump for real-time pH and an Alkatronic that measures both pH and Alk levels every 4 hours. If my alk levels get out of the high or low set points on my Alkatronic then it will test every 2 hours until the levels are back in band.
- This experiment has forced me to allow my alk levels to increase higher than I have been keeping them, so for now my goal is to keep Alk at 9.5 dKH +/- 0.3 dkH.
- I live alone, and don't have a CO2 issue in my home so my pH levels without the Kalk addition don't typically drop below 8.
Goals:
- Keep pH between 8.2 and 8.3 at all times.
- Keep Alk between 9.2 and 9.8 at all times.
Strategy:
- Dose saturated Kalk through a Kalk stirrer every 30 minutes to buffer pH.
- Dose All For Reef every hour to buffer alkalinity (this is a future plan since Kalk is currently keeping my Alk higher than I would normally choose.)
- Use "safety" shutoffs to disable dosing if either pH or Alkalinity levels go to high, or if my return pumps are turned off.
- Use a Dynamic dosing schedule to reduce the amount of Kalk that is dosed when pH nears or exceeds 8.3 to limit the impact on alkalinity.
- Use a Dynamic dosing schedule to reduce the amount of AFR that is dosed as my tank nears 9.5 dKH.
How To:
First thing is the dosing pump. The last time I calibrated it, I was getting 38ml/minute. Because the Hydros has a limit of 500ml/day on a dosing schedule and I know I may want to dose more than that, I'm lying to the controller and telling it that the pump only does 1/20th that amount (1.9 ml/min). That setup looks like this. Since I am gaming the flow rate, I include the multiplication factori n the pump name "(20X)".
The next part of the setup is the safety shutoffs for pH, Alkalinity, and return pumps. To do this I setup 3 generic outputs. DT dKH high is set to turn on if alkalinity goes above 9.7 and it will stay on until alkalinity drops below 9.6.
DT pH High is set to turn on if my main pH probe goes above 8.4 or my Alkatronic pH goes above 8.5 (it typically runs 0.1 higher at the moment). It will stay on until both pH measurements are below their low point settings (8.3 and 8.4.)
The final safety is DT RP Status which is on as long as both of my return pumps are running. I use this for many things like deciding if the skimmer needs to shut down, but I also don't want to dose kalk if the return pumps are not running normally. That configuration looks like this
To make a decision based on all three of these safety inputs, I created a combiner named DT Kalk Ctrl that will show as On if the return pump status is on and both the DT dKH High and DT pH High outputs are off (note the Inverse Input setting for those to items.)
Finally, I setup a Dynamic Dosing schedule that will dose at a rate of 7 litters/day when pH is at or below 8.1 and at 1 litter/day when pH is at or above 8.3. Remember that the actual amount dosed is 20X greater than what is shown in the configuration because I lied to the controller about the speed of the pump.
Finally, I use the Depends On field on the dosing schedule to disable the schedule, and thereby turn off dosing, when the DT Kalk Ctrl combiner control goes off. A couple of other things to note here, since my Alkatronic only checks alkalinity at the top of the hour, I wanted to skew when I dosed the Kalk, Since I'm dosing 48 times a day, or every 30 minutes, I have the dosing schedule setup to start at 15 minutes after midnight so my dosing happens at 15 and 45 minutes after the hour.
A couple of things not documented here are the AFR dosing because I've not actually set that up yet. Also, the kalk stirrer mixing motor. I recently hacked my Avast kalk stirrer to use a magnetic mixer because that slow grinding noise of it's 24/7 motor was driving my nuts. At the moment I am using a simple schedule to run the magnetic stirrer for 45 seconds every 30 minutes at 20 and 40 minutes after the hour. This keeps everything mixed up but allows the slurry to settle enough before the dosing starts.
I haven't experimented with the built in Kalk Stirrer setup in Hydros but I don't think you can use it with a dynamic dosing setup.
So, all-in, this is a lot of setup, and I don't really know if it is worth it. Part of my enjoyment of the hobby is doing this kind of stuff, and I know that is not true of everyone. However, I hope you find this useful. I'm happy to answer any questions you might have and I'd welcome any feedback on what could make this better.
Thanks, Scott
