A calcium reactor for me

[dandy7200]

So I haven't built anything for myself in the last two years and I have been feeling a little left out I have been using two part for the last year after selling the calcium reactor that I had previously built for my system. I have been happy with the results up to a point but honestly feel that the calcium reactor route was less work and a little more reliable. So, here it goes.....

 

I pretty much want to design the best possible reactor in the world, yes the whole world. I don't care how much it cost, I am not trying to sell them, I just want to push the limits of efficiency and design something a little different. I know there are a ton of you here that understand the inner workings of calcium reactors so I thought I would post here and hopefully it will lead to good discussions like the ozone reactor build did.

 

Design goals:

 

1. Recirculating water flow in main chamber

2. Recirculating co2 that is simple and reliable

3. Integrated self filling bubble counter that never requires maintenance

4. Co2 premixing chamber that actually works

5. Internal ph probe

6. Second full size media chamber for effluent

7. Post effluent media chamber for phosphate removal media

8. ???

9. ??

10. ?

 

 

I built the lid and top keyhole flange earlier this week to fit 6" diameter acrylic tube since I have a ton of it right now, I thought it was a good choice.

 

 

To make the domed lid, I baked the 3/8" thick cast acrylic sheet at 285 for 1 hour. Then I put it in a form I made, pressed it in and let it cool. I screwed that part to the work table and did the keyholes and the holes for plumbing on the CNC. It could be done by hand but just be sure to do the machining after the part has been molded since it will shrink a bit in the heating/cooling process. The picture is of the first one I did, I didn't have the clearance high enough on the router and I nicked the left side of the dome, by the third attempt though, I got it right The top center is drilled and tapped for 1/8" NPT John Guest fitting and will be for the co2 recirculation, there are other holes in the lid for 3/4" plumbing and a ph probe holder.

 

I took the day off today and got some time to play around with a mock up of my first thoughts for the design. Actually, these are probably my 30th thoughts on the design but I feel like I am finally making some progress.

 

 

The main chamber and second chamber are both 22" tall and should hold about 20# of media each.

I am using a panworld px40 pressure rated pump mounted below the reactor.

The footprint is 17"x12" and 30" overall height. It's big.

 

The co2 intake is connected to the top of the bubble counter which is connected to the plumbing by a double tee. This is the self filling bubble counter feature that I have used in the past and the same as koralin, geo, etc.

 

Also attached to the doubble tee is another John guest fitting for the water intake. I have several 1/4" tube valves on my main pump manifold so that is how I plan on getting water to the reactor.

 

 

The co2 mixing chamber is stealing heavily from the ozone reactor build, it is a 3.5" diameter chamber that is 12" tall. I filled it with bio-bale and the internal plumbing is pretty much exactly like the ozone reactor. The "pressure relief valve" on this reactor is actually going to be the effluent out of main chamber to the second chamber then to a phosphate chamber and then drip to tank.

 

There is a gate valve after the mixing chamber that should allow me to throttle back the flow and dial in the pressure so that the chamber mixes just like the ozone reactor did.

 

All of that is on the intake plumbing of the recirculating pump. The output of the pump comes up through the main chamber of the reactor.

 

I am thinking about adding a small air pump to the bottom of the second media chamber to help blow off any remaining co2. I am also giving some serious thought to just adding a skimmer pump to the second chamber and using it to recirculate as well as draw air into it via an aspirating venturi.

 

I haven't figured out where I want to put the phospahe removal media chamber, I may leave it as a separate reactor all together. I'm headed to Oregon for a few days so I should have about 20 hours on a airplane to figure it out......

[dandy7200]

I think I may run the water through the top of the mix chamber straight out the bottom and eliminate the valve bypass. The more I think about it, I think that the co2 and water mix should be done in a non pressurized reaction chamber. The goal would be to have a very low ph water solution that didn't have and large co2 bubbles mixed inot it, and thus prevent the slurping sound of the paddle impeller trying to mix the full size bubbles from the co2 that would normally be present. That might free up a little space for me to work in a phosphate media chamber too.

[lanman]

Whereabouts in Oregon? I just got back from Portland/Seaside/Astoria.

 

bob

[dandy7200]

Whereabouts in Oregon? I just got back from Portland/Seaside/Astoria.

 

bob

 

Medford. Grandma's 80th birthday party/ family reunion.

[Sikryd]

Sweet Dan!

 

Nice little setup. I'm looking to get a calcium reactor for my new tank. I wouldn't mind getting something like this with the ozone in it too. Are you building anymore of these or would you?

[flowerseller]

Looks neat naD.

 

# 8. 30th thoughts - say this 10 times really fast

# 9. Add a drain off system?

 

Why a second chamber for effluent? I realize the "old" idea to up the effluent pH returning to the tank. New idea(s)?

Might this not be realized via "air" injection, similar to CO2 injection, and then flow into the phospate media?

Untried, but my first thought of the ozone injection method for CO2 might create havock and an unstable effluent exit flow.

This might make it harder to visually adjust to the traditional method of drip or stream.

[davelin315]

Dan, looking at your design it eliminates one of the problems, at least to a certain extent, that I always experience in my reactor. With a conical lid, any excess bubbles of CO2 or buildup will get put right back into the mix as long as you have a completely smooth transition from one stage to the next. What ideas do you have for an automatic bleed off valve, if this would even be possible, off of the CO2 mixing chamber, hopefully eliminating any bubbles to begin with? The issue that I see with the bubbles building up, which I don't necessarily see happening in your main chamber but possibly after that, is that when they do get mixed in they will throw pH off, at least temporarily. Another issue that I see is that your pump draws directly from the bottom of the main reaction chamber, at least it looks to be that way. What will you do to remove the inevitable pieces of material that get pulled into the pump? How about ideas for a flow through reactor like the carbon reactor that you built for me? You could use the conical top to eliminate bubbles, recirculate from there, and simply tap off of that line for your feed and effluent lines.

 

I understand getting better saturation with ozone by using pressure, but will this really be necessary for a calcium reactor? Is there an advantage to doing that (perhaps the aforementioned removal of bubbles)?

 

I may be misunderstanding your explanation on flow through the system or perhaps reading into fittings that seem to be in different places in different pictures, can you provide a picture that diagrams your flow pattern?

[davelin315]

# 9. Add a drain off system?

 

Why a second chamber for effluent? I realize the "old" idea to up the effluent pH returning to the tank. New idea(s)?

Might this not be realized via "air" injection, similar to CO2 injection, and then flow into the phospate media?

Untried, but my first thought of the ozone injection method for CO2 might create havock and an unstable effluent exit flow.

This might make it harder to visually adjust to the traditional method of drip or stream.

I agree, a drain off would be nice to have and is an easy addition to this (I use mine all the time on my geo reactor).

 

Also, I am only guessing, but since GFO is iron based, won't the effluent from the reactor create issues there? I'm thinking of calcification of the GFO and also degradation based upon the acidic nature of the effluent. Even with a second effluent chamber, do you feel that the contact time will allow it to actually get back to where you want it?

[davelin315]

Oh, and when are you going to sell retrofit lids for my geo reactor so that I can resolve the issue I just mentioned?

[Jon Lazar]

I'm headed to Oregon for a few days so I should have about 20 hours on a airplane to figure it out......

 

Are you flying in a rubber-band airplane?

[dandy7200]

Sikryd, I don't really have plans to sell these. Even if I ever decided to it would be a long time from now. I do plan to have a calcium reactor kit available in the next few months and if this reactor comes together well I will definitely offer the domed lid as an option.

 

Chip, the "new" thoughts on second media chamber are the same as the "old" ones. Water drain or co2 drain/bleed like Dave is talking about? I drilled holes for guest fittings in the base plate so I could drain it for maintenance. If I go with the pressurized injection (which I m leaning away from) effluent would go into the top of the second chamber and the effluent flow would come out the bottom. The feed for the drip would need to be below the top of the second chamber and there would be a small hole drilled to let out the pressure in that second chamber as well. That combo would keep the water level in the second chamber even with where I placed the effluent drip on my system and it would create a air free gravity feed effluent so there would be no spray issues. In order to add air to the second chamber via pump or venturi, it is necissary for the second chamber to be "open" or not pressurized, the co2 needs a place to "escape". So that is the only "new" idea on my second chamber, I don't think the "old" style second chamber gives the co2 any place to vent to it relys solely on a additional contact time soak it up.

 

What I m concerned about with pressurizing that chamber is that since the main chamber recirculation is essentially a closed loop, the valve restriction wont actually work since it will be valving the input as well as the output. Some of that additional pressure needed to actually make it work will come from the water input and co2 input but I am not sure it will be enough.....

 

Dave, the entire purpose of the conical lid is to eliminate the need for a bleed off. It will instead recycle the co2 rather than cause a pressure build up or "slurp" it into the recirc pump or worse release it into the effluent. This system should be less maintenance and more efficient than than the geo.

I don't want any co2 bubbles to build up at all on the intake of the pump, that is the reason for the preinjection chamber, if it is 100% full of water and the bubbles have a chance to mix inside the biobale media then it will create (hopefully) a saturated water mixture before being sent to the pump, so yes, the purpose of the injection chamber is to eliminate bubbles. The pump actually draws from the top of the chamber, the output is under the main chamber. All the injection, mixing, recirculating of co2 happens on the input side of the plumbing.

 

I have no idea how GFO will react to dkh 30 and 800ppm calcium Maybe you could put a little in a cup and drip your calcium reactor effluent over it for a bit and see what happens. I don't predict anything odd happening but you never know.

 

Jon, a big town Medford is not. 3 connections both ways and rubberbands might be driving the props of the last one I took to get here.

[zoozilla]

Oh, and when are you going to sell retrofit lids for my geo reactor so that I can resolve the issue I just mentioned?

 

+1.

[dandy7200]

+1.

 

Would actually be quite easy. Probably a good market for upgrade parts for that particular reactor. It is without a doubt the most popular calcium reactor in the US. I would need to borrow someones reactor for a hour or so to match the keyhole dimensions, but once that was done it would be easy machining. The installation would be simple too since the geo uses that bit of soft tubing on the input of the pump. I would just need to match the union he uses on the lid. Hmmm, I like that idea a lot

[ctenophore]

How about adding an effluent stem about 3-4" below the domed lid, with either a U or a bell on the bottom to prevent small CO2 bubbles from leaving with the effluent. Don't rely on the recirc pump to push effluent to the second chamber for this same reason. The whole reactor would need to be driven by a feed pump or a pressure feed from a tee'd main return pump.

 

Design the second chamber to hold very fine media, possibly even aragonite sand. The slow flow (bottom up?) would ensure maximum CO2 usage. I'm not sure how the fine sand would work, you might get mud at the low-pH end of this chamber. The pH should climb to nearly normal levels by the time it exits this stage though. Maybe mud would be okay though- we're not trying to recirculate here, so the finer the surface area, the better the CO2 reaction. You might get detritus buildup in here though unless you put a prefilter on the entire unit.

 

Depending on how much (if any) CO2 builds up in the second chamber, maybe add a second domed lid with a recirc tube, except put this one on a timed solenoid so that it only opens to suck the excess CO2 once or twice a day. That would prevent vapor locking the second chamber's effluent line.

[dandy7200]

I am planning on feeding the reactor from the main pump, I like the idea of smaller media in the second chamber. Crushed coral maybe?

 

Honestly I think that the dome lid with the co2 recirculation loop will be so much more effective than the current standard that I will probably not have to worry too much about the effluent ph. I am betting that the amount of co2 required to maintain a consistent ph inside the reactor will be about half of what it is with a traditional lid. I think the biggest reason for me putting the second chamber in is to produce more calcium/alk. No since in wasting it. I think I am going to play around in illustrator a bit and see if I can make a nice GSA sticker that looks something like this to put on it when I'm done:

 

 

 

 

I actually played around with it today a bit and cut some more parts, figured out a nice way to get the 3rd chamber in there and have it look nice. Trying to visualize the 1/4" plumbing so I can design some tube routing into it and keep it neat looking. I also found a 6" piece of 2.5"diameter tube to make a nice big bubble counter with. This thing is going to need some bracing as well, all the chambers are going to need to be tied together somehow so the base doesn't flex at all when it has 50# of water and media in it. Maybe I should just put casters on it too :P

[davelin315]

Would actually be quite easy. Probably a good market for upgrade parts for that particular reactor. It is without a doubt the most popular calcium reactor in the US. I would need to borrow someones reactor for a hour or so to match the keyhole dimensions, but once that was done it would be easy machining. The installation would be simple too since the geo uses that bit of soft tubing on the input of the pump. I would just need to match the union he uses on the lid. Hmmm, I like that idea a lot

You can borrow mine! It's currently offline while my calcium and alk have gone through the roof. It's essentially just turning into a nitrate factory sicne there's no CO2 being introduced (and may not have had any for a long time since my probe is obviously way off). Let me know if you want to borrow it to do this and we'll figure out a time to have me drop it off.

[dandy7200]

You can borrow mine! It's currently offline while my calcium and alk have gone through the roof. It's essentially just turning into a nitrate factory sicne there's no CO2 being introduced (and may not have had any for a long time since my probe is obviously way off). Let me know if you want to borrow it to do this and we'll figure out a time to have me drop it off.

 

Sounds like a plan. What brand of union is on it? Threaded or slip?

[davelin315]

I'll have to check, I'll shoot you a PM.