Unconventional Calcium Reactor for the average reefer!!

[reefwiser]

The problem you will find with that regulator is it will not tell you when your Co2 has run out. An in a CalRX with Co2 running all the time the small bottles don't last long. I use Co2 in my planted tanks and the Paintball bottles Last a good while because you are only running Co2 while the lights are on. The Yeast method does give you consistent Co2 so it is useless.

 

[McDam]

The problem you will find with that regulator is it will not tell you when your Co2 has run out. An in a CalRX with Co2 running all the time the small bottles don't last long. I use Co2 in my planted tanks and the Paintball bottles Last a good while because you are only running Co2 while the lights are on. The Yeast method does give you consistent Co2 so it is useless.

As the CO2 runs out and drops below 5 psi wouldn't the output pressure also drop and that would be indicated on the regulator, no?
I am not to worried about it. I monitor pH in the reactor so I will know when it can no longer maintain pH and it has run out.

 

[KenO]

As the CO2 runs out and drops below 5 psi wouldn't the output pressure also drop and that would be indicated on the regulator, no?
I am not to worried about it. I monitor pH in the reactor so I will know when it can no longer maintain pH and it has run out.

The problem with CO2 tanks is not running out, it's the point right before you run out. On a standard CO2 pressure regulator with a high pressure side and a low pressure side, you would set the low pressure and adjust your bubble count. As the tank loses CO2 the high pressure side will start to drop, when that happens the low pressure side tends to go up in pressure. Which increases the bubble count because you now have more pressure on the low side. So over time you have to keep tweaking the low pressure side back down. When the high pressure side really drops low, you can get whats called an end of tank dump. The low pressure side jumps up, bubble count goes way up and you end up dosing a bunch of CO2. If you are using a pH controller it will detect the drop in pH and shutoff your solenoid. If you are not using a pH controller, then you will have a bunch of fish gasping for air at the top of the tank, or worse dead fish.

 

[KenO]

My reactor arrived late yesterday. Opened the box today to test it out and to install the fitting I need to inject the CO2 from the soda bottles. One big problem, the thickness of the reactor lid is too thick for the gland fitting I was going to use. So plan B, I took a RO fitting that I had laying around and drilled a hole for it to fit. I needed to silicone around the fitting, so I am going to have to wait for the silicone to cure before I can test it out. I was pretty impressed with the flow inside of the reactor. I tested out the needle valve that I have to control the flow and it looks as if it is going to work just fine.

 

[KenO]

I also have an inline RO style check valve that I am going to put on the output of the CO2 bottles and into the fitting I put into the lid. The check valve should keep the water in the reactor from going into the CO2 soda bottles when the CO2 level drops too low. At least that's the idea.

 

[McDam]

The problem with CO2 tanks is not running out, it's the point right before you run out. On a standard CO2 pressure regulator with a high pressure side and a low pressure side, you would set the low pressure and adjust your bubble count. As the tank loses CO2 the high pressure side will start to drop, when that happens the low pressure side tends to go up in pressure. Which increases the bubble count because you now have more pressure on the low side. So over time you have to keep tweaking the low pressure side back down. When the high pressure side really drops low, you can get whats called an end of tank dump. The low pressure side jumps up, bubble count goes way up and you end up dosing a bunch of CO2. If you are using a pH controller it will detect the drop in pH and shutoff your solenoid. If you are not using a pH controller, then you will have a bunch of fish gasping for air at the top of the tank, or worse dead fish.

Very interesting. I had no idea.
I also put a check valve on the CO2 line today. To prevent any back flow between the reactor and pump.

 

[reefwiser]

Yes it is called Co2 dump and its the reason why you use a good set of gauges.

 

[McDam]

I am assuming this won’t be an issue since the dosing pump will stop any dump. In fact it should just keep running until it is pulling a vacuume on the bottle.

Can’t wait to see it in action KenO. That bottle setup is so neat. What kind of pressure have you been able to get with it?

 

[KenO]

I am assuming this won’t be an issue since the dosing pump will stop any dump. In fact it should just keep running until it is pulling a vacuume on the bottle.

Can’t wait to see it in action KenO. That bottle setup is so neat. What kind of pressure have you been able to get with it?

Off the top of my head, I don't remember the pressure, but the bottles do get hard. The one time I had stopped using the CO2 for about 2 months. I had closed off the metering valve on the output and the bottles sat sealed up for the 2 months with the citric acid and baking soda in them. When I opened the metering valve, the CO2 starting flowing. I was very impressed that it held the pressure and was able to continue making CO2 after sitting that long. I don't think that from a space saving perspective the soda bottles are going to save any space vs a small CO2 bottle, but it will be fun to try. I do have a 5lb CO2 bottle that I need to get filled, plus I have all the pressure gauges, etc.

 

[KenO]

So I went and looked at the gauge on the soda bottle setup. I remember the gauge being in the green zone. It is in kg/cm2 and was around 2, which translates to about 28 psi.

One thought regarding the tubing on your dosing pump. CO2 will leak through certain types of tubing. In addition over time CO2 will also breakdown certain tubing materials. Whenever I've used CO2, I would also get the tubing rated for CO2.

 

[garbled]

I did stumble on some info on using yeast while reaserching CO2 applications. But haven’t had the time to look into it. I thought it might be hard to regulate or give consistent resaults. But another option forsure.

I've tried to build a yeast generator. It's super fiddly. It's very hard to regulate the amount of CO2 produced. Eventually, it grows to a point where it kinda goes nuts and generates a ton of CO2, then dies off.

If you look into commercial solutions for regulating yeast, you find that it is a bajillion dollar industry, and not for the faint of wallet.

 

[KenO]

I tested my modified lid with the RO fitting on it. No leaks. Running the reactor without anything else attached right now just to make sure everything looks good. I will hopefully get something running tomorrow.

McDam I know you have measured the pH level in the reactor, have you measured the dKh of the effluent coming out of it? I remember reading that you want the dKh of the effluent to be around 24.

 

[McDam]

I have measured it previously for the past setups but not since I installed the sodastream bottle. I have been adjusting the dose to see where the ph will stabilize. I will test tonight if I get a chance. But I did test alk to make sure there was no spike and it has been consistently around 8.4

 

[KenO]

I got the soda bottle CO2 hooked up today. I will post pictures tomorrow. I had to make a make shift bubble counter. I needed to see how much CO2 was going into the system. Tomorrow I will measure the ALK level of the effluent. I also need to hook up a pH meter to see what the pH level is inside the reactor.

 

[McDam]

Just Did some testing this morning.
Effluent dripping at 14 ml/min
25.2 dKH or 9 meq/L

Display
Alk : 8.68
Cal: 370
Mag: 1280

 

[KenO]

Just Did some testing this morning.
Effluent dripping at 14 ml/min
25.2 dKH or 9 meq/L

Display
Alk : 8.68
Cal: 370
Mag: 1280

25.2 dKH is a great number.

I needed to up the CO2 flow, the effluent was reading a pH of 7.6, not low enough to start dissolving the media.
I still need to get the pH meter calibrated and put the probe into the top fitting.
I will also measure my drip rate. I think I'm running higher than 14ml/min.

Pictures are coming.....

 

[KenO]

So I adjusted the bubble flow through the world's largest bubble counter (see picture) and was able to get the pH down to 6.4. I made an adjustment, came back later and the pH went back up to 7.7. The adjustment valve on the output of the CO2 soda bottle is not going to let me make the fine adjustments that I need. It makes CO2, but it's not going to work long term. Tomorrow I'm planning on getting one of my 5lb CO2 bottles filled. It will take a couple of days, since the place I take the bottle to has to send the bottle to a central location for filling. So I should be able to pick it up by Friday. Then I will hook that up to get a more consistent bubble count. The reactor does work if you are able to give it a consistent amount of CO2.

For filling the CO2 soda bottle, you put 200grams of Citric Acid in 600ml of water in one bottle. The second bottle gets 200 grams of baking soda in 200ml of water. The citric acid/water mixture will be clear and the baking soda one will still have a slurry of baking soda in it. The bottle with the citric acid/water gets the fitting with the pressure gauge. The other fitting goes on the baking soda bottle. To prime the system, you close the output valve and then squeeze the bottle with the citric acid/water mixture, this will force some of the solution to flow through the tubing into the bottle with the baking soda and it will begin to make CO2. You do this a number of times and pressure will build in the system. I was able to get the pressure to 1kg/cm2 which is about 14 psi. Then when you open the output valve and let the CO2 gas start to escape, the pressure will drop slightly, and the citric acid/water mixture will get pulled through the tubing into the baking soda bottle. When it does the reaction will make more CO2 and the pressure buildup will stop the flow of the citric acid/water mixture. This process repeats over and over as CO2 is released and the pressure drops and builds. It does work really well.

To see the bubbles, I only had this clear RO fixture, so I put water in it to see the CO2 bubbles. It works, but it is huge.

 

[McDam]

So I adjusted the bubble flow through the world's largest bubble counter (see picture) and was able to get the pH down to 6.4. I made an adjustment, came back later and the pH went back up to 7.7. The adjustment valve on the output of the CO2 soda bottle is not going to let me make the fine adjustments that I need. It makes CO2, but it's not going to work long term. Tomorrow I'm planning on getting one of my 5lb CO2 bottles filled. It will take a couple of days, since the place I take the bottle to has to send the bottle to a central location for filling. So I should be able to pick it up by Friday. Then I will hook that up to get a more consistent bubble count. The reactor does work if you are able to give it a consistent amount of CO2.

For filling the CO2 soda bottle, you put 200grams of Citric Acid in 600ml of water in one bottle. The second bottle gets 200 grams of baking soda in 200ml of water. The citric acid/water mixture will be clear and the baking soda one will still have a slurry of baking soda in it. The bottle with the citric acid/water gets the fitting with the pressure gauge. The other fitting goes on the baking soda bottle. To prime the system, you close the output valve and then squeeze the bottle with the citric acid/water mixture, this will force some of the solution to flow through the tubing into the bottle with the baking soda and it will begin to make CO2. You do this a number of times and pressure will build in the system. I was able to get the pressure to 1kg/cm2 which is about 14 psi. Then when you open the output valve and let the CO2 gas start to escape, the pressure will drop slightly, and the citric acid/water mixture will get pulled through the tubing into the baking soda bottle. When it does the reaction will make more CO2 and the pressure buildup will stop the flow of the citric acid/water mixture. This process repeats over and over as CO2 is released and the pressure drops and builds. It does work really well.

To see the bubbles, I only had this clear RO fixture, so I put water in it to see the CO2 bubbles. It works, but it is huge.

Great Info #KenO, I had a thought, since you mentioned that you had purchased a kamoer did you consider hooking it up to try and regulate the CO2. It should give you the fine adjustments you need at low speed, plus allow the CO2 to build up and stay a bit more consistent within the bottles without releasing pressure into the reactor. And as it pulls it should regulate the addition of acid to the baking soda in a more consistent manor? Worth a shot if you are still waiting on the CO2 fill up. Another thought in conjunction with this would be to reduce the size of tubing to help restrict volume of CO2 flow.

 

[McDam]

So, the SodaStream bottle ran out. It lasted a little over a month. Using it first to make CS than later connecting directly to the reactor. Plus, about 20+ L of personal consumption. I am hoping to get 2 months out of a full bottle, but time will tell.

Using the peristaltic dosing pump for the CO2 regulation has been working flawlessly and avoided any CO2 dump at the end of the CO2 supply. I am still wondering why this method is not being used. Is it simply a new concept? Can experienced people with calcium reactors chime in? Is there a reason that I am not seeing?

I have received my continuous dosing pumps! They are up and running connected to the apex and I am currently testing it out, but I got to say, I am seeing some extremely stable results. One pump is dosing CO2 to the reactor and the second pump pulling fluid through the reactor. Both independently controlled and variable. I was able to program the CO2 pump to dynamically control the pH in the reactor using basic programming in the apex and it was surprisingly simple to set up. Only two cables, power and a regular network cable to the V1/V2 port which makes it compatible with both versions of the Neptune apex. The Pump dosing through the reactor is pulling and is set at a constant speed to match my previous drip rates. As the drip rate is increased the CO2 dosing pump should compensate for pH changes so there is no going back and adjusting bubble counts if you increase effluent rates. So now I am able to control effluent drip rates and CO2 (bubble rates) from anywhere which makes it extremely useful when away from home. I am still waiting on a few pieces of the pump build to arrive, but as soon as I have it all together, I will post some pics. I have a nice teaser video, so I will have to figure out how to post that as well.

And So, another question for calcium reactor users. What is the typical pH swings you see in your reactors and how stable are you able to keep it with a regulated bubble count? What is the end goal and what is just acceptable? Can we see some long-term trends?

 

[McDam]

As I promised here is a short video demonstrating the continuous peristaltic pumps and the control-ability via the apex and APEX Fusion.
Pumps off - 0% - 0 RPM
Pumps on - 100% - 100RPM
Then just to show the variability of speed demonstrated with the ramp function one goes from 0 - 100 the other from 100 - 0 when previewed.

Enjoy

Here is the Reactor pH showing the difference in pH control between the two types of dosing pump. We can achieve a whole other decimal point of accuracy and stability.