Calcium reactor control by Neptune Trident

[Rst]

Hi Tony, so great to have your support. I would normally be guessing as I have been doing up until you have now kindly pointing the way. Calcium reactors are a beast to tame.
Ron

 

[Shirak]

Hi Tony, so great to have your support. I would normally be guessing as I have been doing up until you have now kindly pointing the way. Calcium reactors are a beast to tame.
Ron

Hi Ron,
Happy to help!

 

[Rst]

Hi Ron,
Lets give it a day. Your starting in the morning at 8.93dkh and the throttle code is running. A 24hr cycle from this point will be good information to see where the alk levels go through a light cycle and where they end up tonight and tomorrow morning.
Tony

Hi Tony,
Here again is the complete graph since I started at 9pm Nov2 and when I removed the If pHCaR5 >7.00 statement. To repeat, my Apex variables during this time up until now have been FIXED at Flow=30ml/min; CO2Maxnum=8.90; Throttling 5mins ON 25mins OFF; and 1Bubble every 8mins. I have made no Apex changes since 9pm Nov2.

My latest pHCaR5 vs Alkx17 graph which follows below, starts Nov2 9pm and ends today at approx Nov5th at 3pm.
Test results of the tank's Alkalinity occurred every 3 hours occurs daily starting at 2am,5am,8am,11am, 2pm,5pm,8pm and ending at 11pm.

The latest throttling started at 2:10am Nov4th at 8.90dkh and when throttling ended at 5:10pm Nov4th the current Alkalinity test then had already dropped to 8.70 dkh.

The latest (and last) FULL ON period started at 5:10pm Nov4th testing at 8.70 dkh and ended this afternoon at 2:10pm Nov5th when this test result was 8.91. This FULL ON period lasted 21 hours. The lowest alkalinity tests occurred at 8pm and 11pm bottoming out at 8.62dkh, then rising to 8.67dkh at 2am, 8.76 at 5am, 8.8 at 8am, 8.84 at 11am, and finally rose just above 8.90 at 2pm today. Of course throttling resumed briefly as I now stopped to report.

Hopefully I now have enough data to start fine tuning. Question is, can I reduce the swings and if so how do I go about it?

 

[Shirak]

Hi Ron,
Yes that helps give a better picture of what the reactor and alk in the tank is doing and how the various code is controlling things. How often are you testing and what is your light cycle on/off and ramping up and down?
Will take a better look tonight but will help to know how the testing times and light cycle are interacting with your alk levels and reactor control.
Tony

 

[Rst]

Hi Ron,
Yes that helps give a better picture of what the reactor and alk in the tank is doing and how the various code is controlling things. How often are you testing and what is your light cycle on/off and ramping up and down?
Will take a better look tonight but will help to know how the testing times and light cycle are interacting with your alk levels and reactor control.
Tony

Hi Tony.
My testing times are given in my last post. Testing every 3 hours at 2am,5am, 8am, 11am, 2pm, 5pm, 8pm, 11pm daily.

My lighting starts at 11am at zero % ramping to to 40% at 2pm where it stays at 40% until 7pm when it then ramps back down to 0% at 9pm (10 hr photoperiod)

Ron

 

[Shirak]

Hi Tony.
My testing times are given in my last post. Testing every 3 hours at 2am,5am, 8am, 11am, 2pm, 5pm, 8pm, 11pm daily.

My lighting starts at 11am at zero % ramping to to 40% at 2pm where it stays at 40% until 7pm when it then ramps back down to 0% at 9pm (10 hr photoperiod)

Ron

Hi Ron,

Looking at your Alk levels and what's going on with the reactor control I see the following trend:
During much of the light cycle the reactor is running mostly on throttle. Towards the end of the light cycle the alk has dropped below the cutoff and now the carbon doser is on for much of the night as it catches up to alk use during the day. This is causing it to throttle again in the morning just before lights are coming back up and it's repeating the same cycle. Mine was following the same trends so I added a line that would keep the CO2 on full time during the light cycle when the alk was being consumed.

I would suggest the following line in your CO2_7_5 code after the VO_CO2Limiter line

If Output VO_CO2Limter = ON Then OFF
IF Time 11:00 to 20:00 Then ON
If pHCaR5 < 6.60 Then OFF

This will get the CaRx ramping up alk into the tank as your lights are approaching max intensity and demand is at it's highest. Try that for a couple days and lets see how the cycles go.

As long as you are not going crazy with CO2 while it's on this will help raise the low point you are seeing at 8.68dkh

I would also tighten the high level off line
If Alkx17 > 9.30 Then OFF

Change that to >9.1 Then OFF

 

[Rst]

Hi Ron,

Looking at your Alk levels and what's going on with the reactor control I see the following trend:
During much of the light cycle the reactor is running mostly on throttle. Towards the end of the light cycle the alk has dropped below the cutoff and now the carbon doser is on for much of the night as it catches up to alk use during the day. This is causing it to throttle again in the morning just before lights are coming back up and it's repeating the same cycle. Mine was following the same trends so I added a line that would keep the CO2 on full time during the light cycle when the alk was being consumed.

I would suggest the following line in your CO2_7_5 code after the VO_CO2Limiter line

If Output VO_CO2Limter = ON Then OFF
IF Time 11:00 to 20:00 Then ON
If pHCaR5 < 6.60 Then OFF

This will get the CaRx ramping up alk into the tank as your lights are approaching max intensity and demand is at it's highest. Try that for a couple days and lets see how the cycles go.

As long as you are not going crazy with CO2 while it's on this will help raise the low point you are seeing at 8.68dkh

I would also tighten the high level off line
If Alkx17 > 9.30 Then OFF

Change that to >9.1 Then OFF

Hi Tony,
What you suggest reminds me of how I had to adjust my 2 part dosing where 70% of my demand occurred during lights on. So ensuring that Full ON coincides when lights are on. I have now added the Time command and lowered the safety net to turn off Full On dosing if the Alkalinity goes above 9.1.

Maybe there could be 2 sets of throttling strengths, one for lights on and one for lights out? Just a thought.

I will run this new code tonight and during the weekend. Hopefully this will get me closer to better results.

Thanks for giving so much of your time,
Ron

 

[Shirak]

Hi Tony,
What you suggest reminds me of how I had to adjust my 2 part dosing where 70% of my demand occurred during lights on. So ensuring that Full ON coincides when lights are on. I have now added the Time command and lowered the safety net to turn off Full On dosing if the Alkalinity goes above 9.1.

Maybe there could be 2 sets of throttling strengths, one for lights on and one for lights out? Just a thought.

I will run this new code tonight and during the weekend. Hopefully this will get me closer to better results.

Thanks for giving so much of your time,
Ron

Hi Ron,

you read my mind lol. I run two sets of throttle codes. The high one is designed to let the alk drop slowly if it's over 8.9 but below 9.1 I have another set of codes that will slow the reactor so it's not running full blast but still allow the alk to rise slowly. This second set of codes really is only an issue if the reactor is putting too much alk in. Ideally the CO2 pressure and bubble count should be tuned so that it raises alk slightly or at least keeps up with demand during the day. Can take a while to get those settings just right though.

 

[Shirak]

Keep in mind some of the alk swing between day and night is just normal fluctuation as pH swings between day and night. So I don't think it will ever be perfectly flat. If I can keep my daily swing around .2dkh I am pretty happy.

 

[Recipe2reefing]

Thanks for your input. Actually I first read Marc's blog at the beginning of my journey but I was still not understanding fully. So I sent a question to Marc at melevsreef back on Sep12, 2021 as follows:

[ I don’t understand, when using this same code in your blog, how you ensure that “pH in the reactor is set to 6.8” ? How do you keep the pH fixed at a specific pH level.? Won’t the pH in the reactor always be fluctuating with no real fixed level? Is there some additional Apex code that you are using to keep this pH set somehow? ]

Marc did kindly reply saying that that was a very good question. He then went on to say that he had no idea how the pH is set to 6.8. He said this code was provided to him by another member on R2R. But suggested that I go and find a thread on reef2reef which discusses this code. ie this thread and this is how I landed here.

I have spoken to Richard Ross and message marc and they have had a good discussion about it.
Marc has added the ph code to his blog last week.
The issues Is a different one .I didn’t understand why the reactor wasn’t turning off when the alkalinity reached the desired level. I was of the understanding that I would turn off when it’s above alk levels and use the timing code what is was under all levels. In fact I worked out that is not meant to do that but rather use the timer when it’s above desired alkalinity and be on nonstop when it’s below. Now that I understand that I am following Marc’s blow down to the T. I want to thank them again for helping and being really nice.

 

[Rst]

I have spoken to Richard Ross and message marc and they have had a good discussion about it.
Marc has added the ph code to his blog last week.
The issues Is a different one .I didn’t understand why the reactor wasn’t turning off when the alkalinity reached the desired level. I was of the understanding that I would turn off when it’s above alk levels and use the timing code what is was under all levels. In fact I worked out that is not meant to do that but rather use the timer when it’s above desired alkalinity and be on nonstop when it’s below. Now that I understand that I am following Marc’s blow down to the T. I want to thank them again for helping and being really nice.

HI,

At the super helpful and much appreciated guidance of another member Shirak here in this thread, my Apex CO2 outlet code was changed such that I no longer use the current pH level in the reactor as a control variable.

So my CO2 outlet code previously was:

Fallback ON

SET ON

If pHCaRx > 7.0 Then ON

If Output CaRx-limiter = ON Then OFF



My current CO2 outlet code is now:

Fallback ON

SET ON

If pHCaRx > 7.0 Then ON

If Output CaRx-limiter = ON Then OFF

If Time 11:00 to 20:00 Then ON



This last apex statement forces the CO2 outlet to switch to stay full ON at max CO2 continuously during my lights ON photo-period. This really helped keep the Alkalinity swings down significantly to within 0.2 dKH daily. NOTE: This code works ONLY WHEN you have already previously found your ideal fixed settings of your other CO2 Reactor variables. In my case, these other variables are fixed at 1 Bubble every 8 seconds and 30 ml/min flow. Naturally every reactor is different and these fixed variables are strictly limited to my reactor.

Ron

 

[Rst]

Note: The cross out line in my last post is not clearly visible. The statement If pHCaRx > 7.0 Then ON should be deleted in my new outlet code.

 

[Rst]

Keep in mind some of the alk swing between day and night is just normal fluctuation as pH swings between day and night. So I don't think it will ever be perfectly flat. If I can keep my daily swing around .2dkh I am pretty happy.

Hi Tony,

Below is my pHCaR5 VS Alkx17 graphed results over the last 3 days:

I think these are very impressive results! I am going to keep the status quo for the rest of the week and see how it goes. If all goes well, my goal is to raise my Alkalinity set point from 8.90 dkh currently up to 9.5 or so. Hoping that this doesn't cause any major adjustments other than one simple code change.

I started this calcium reactor struggle Aug 2021. My quest to control this reactor was never achieved until and only through your very kind directions and at the expense of too much of your time. All I can say is a huge THANK YOU>

Ron

 

[Shirak]

Hi Tony,

Below is my pHCaR5 VS Alkx17 graphed results over the last 3 days:

I think these are very impressive results! I am going to keep the status quo for the rest of the week and see how it goes. If all goes well, my goal is to raise my Alkalinity set point from 8.90 dkh currently up to 9.5 or so. Hoping that this doesn't cause any major adjustments other than one simple code change.

I started this calcium reactor struggle Aug 2021. My quest to control this reactor was never achieved until and only through your very kind directions and at the expense of too much of your time. All I can say is a huge THANK YOU>

Ron

Hi Ron,

Looking good. You could keep it like that for now if you want. Should be able to just bump the numbers up to 9.5 range if you want to keep a higher level. Should not affect the performance too much.

Your alk is still dropping a little during the day with the reactor running at 8sec/bubble when the lights are up at your max setting. The bubble count is pretty slow so you get a fairly gentle downward curve when the CO2 is on. You could try upping the bubble count to maybe 7sec/bubble. It will give you a slightly steeper drop on the reactor pH when it goes full on at 11am which will bring it up to speed a little faster as the lights ramp up. You just need to watch it doesn't spike too high at night. As it is now it's taking until about 2am for your reactor to catch up to the days usage and hit the throttle code. A little faster bubble count SHOULD give you a little less downside during the peak of the light cycle and an earlier trigger on the throttle. The risk is it could spike alk a bit higher at night. An alternative is to start the time on cycle a little early, maybe something around 10am instead of 11.

The nice thing is now that you have it working pretty much where you want it you can make small adjustments and see how the tank alk reacts.

 

[Rst]

Hi Tony,
I certainly would prefer if the pH in the reactor would drop quicker from its peak at 11am. That way, I could supply stronger effluent when it was needed the most during the mid afternoon.
I will try to mitigate this, as you have suggested.

Thanks

 

[Rst]

Hi Tony,
I certainly would prefer if the pH in the reactor would drop quicker from its peak at 11am. That way, I could supply stronger effluent when it was needed the most during the mid afternoon.
I will try to mitigate this, as you have suggested.

Thanks

I have now left the reactor untouched for the last 5 days. The last and only change I made was at Tuesday Nov 9th 10am, when I increased the bubble count from 1 bubble every 8sec to every 7sec. All other settings were as before: Flow=30ml.min; and forced Full ON with command If Time 11:00 to 20:00 Then ON

It does seem to me that changing the bubble count didn't really make much difference, and that the new bubble count of 1 bubble every 7sec might have had a little more variance(0.2 dkh) than on Nov 6,7 & 8th(0.1 dkh) .

I was hoping that this change might of increased the strength of the effluent over the afternoon peak demand but it seems that the speed and level of the pH dropping is not occurring when needed the most.

Nevertheless, do not think that I am unhappy with the results, because the reactor is definitely doing its job.

I might now try forcing the Full ON to occur 1 or 2 hours earlier, ie from 9 or 10am instead of 11am.

 

[Shirak]

Hi Ron Yes not a big change going from 8sec to 7sec interval. I have my on time set about an hour before the lights start to ramp up. My ramp time is only 30 min. Your pH drop is also influence by the secondary pressure controlled by the knob on the Carbon Doser. Higher pressure will give you a bigger bubble with each count. I would try with changing the on time first and maybe later try dropping to 6 seconds. Best not to mess with the pressure settings if you can help it. Eventually though you may need to if demand is not kept up with and the bubble count is very quick. Then it's time to up the pressure just a bit.

No matter what you do there will be some variance from day to day, .2-.3 swing is pretty good over a 24hr period.

 

[Rst]

Hi Ron Yes not a big change going from 8sec to 7sec interval. I have my on time set about an hour before the lights start to ramp up. My ramp time is only 30 min. Your pH drop is also influence by the secondary pressure controlled by the knob on the Carbon Doser. Higher pressure will give you a bigger bubble with each count. I would try with changing the on time first and maybe later try dropping to 6 seconds. Best not to mess with the pressure settings if you can help it. Eventually though you may need to if demand is not kept up with and the bubble count is very quick. Then it's time to up the pressure just a bit.

No matter what you do there will be some variance from day to day, .2-.3 swing is pretty good over a 24hr period.

Hi Tony,
I didn’t know that the bubble size is influenced by the pressure knob on my on the carbon doser. Good to know. My secondary pressure is set to 15lb and seems steady but my bubbles are very big in size.
Yes tomorrow my ON time will now start 1 hour earlier ie 10am. We will see if that helps. And know that when I was working with 2 part dosing, I would be lucky If I only had a 0.2 dkh difference during the 24HR period. Usually it was more and sometimes a lot more.

 

[Rst]

Hi Ron Yes not a big change going from 8sec to 7sec interval. I have my on time set about an hour before the lights start to ramp up. My ramp time is only 30 min. Your pH drop is also influence by the secondary pressure controlled by the knob on the Carbon Doser. Higher pressure will give you a bigger bubble with each count. I would try with changing the on time first and maybe later try dropping to 6 seconds. Best not to mess with the pressure settings if you can help it. Eventually though you may need to if demand is not kept up with and the bubble count is very quick. Then it's time to up the pressure just a bit.

No matter what you do there will be some variance from day to day, .2-.3 swing is pretty good over a 24hr period.

Hi Tony,
Just after I messaged you last, I went out and purchased a dozen new frags. I should have expected some demand changes but somehow I only reacted after the fact.

So I decided that this might be a opportunity to to run my tank at a higher alkalinity, and so lot has changed over the last week. Firstly I lowered my Alkalinity testing to 6 times/day from 8. This affected my testing schedule to be at 1am,5am,9am,1pm/5pm & 9pm. I also increased my bubble rate from 1 bubble every 7 secs to 1 bubble every 6. I increased my Alkalinity goal up to 9.50 from 8.90. It was a little scary but all in all, my tank's alkalinity is still mostly under control but with a few unexpected ups and downs.

Here is this weeks changes:

I am still trying to determine how to limit the larger swings.

Ron

 

[Shirak]

Hi Ron,
May take some time to settle down yet. I run 6 tests also and the longer span between tests will give a bit more up and down on the Alk. Looks like it's spiking a bit at late night which you could try upping to 6.5 seconds on the bubble count and changing the on time command to 30 minutes earlier and 18 off instead of 20. That might help keep the low side up towards 9.5 and reduce the light nigh overshoot.