My requirements (in addition to the basic requirements of any good CA reactor) were that it could not look too "rigged" or hokey (no offense, but toilet flanges were not my cup of tea) and it had to have a good, two chamber design that maximized my available space.

 

Below are a couple of the docs I used to design it up and today I picked up my acrylic from Delvies Plastics downtown. Tomorrow I will be putting it together with the help of plastics-expert  Dave Anderson out at his place. Hopefully I will have a good portion of it done and we will have it at Dave's table at the club meeting.

 

All in (plastic, fittings, pump, CO2 tank, regulator, solenoid, bubble couter, etc.) is coming in at under $300 so that makes me happy.

 

I will post photos of some of the fabrication soon.

Sculpin

 

If you have any demand for alkalinity/calcium, then a simple method to drip kalkwasser into your aquarium is, IMO almost a must.  You're adding top off anyway, why not make it work for you in two ways? (stable salinity AND alk/calc additions)

 

Just for your info, the pH of the effluent leaving the kalkwasswer reactor is about 12, while the pH of the effluent exiting my calcium reactor was about 7.

Just a thought.

Sculpin

Here are some notes and following that are some photos.

Issues that arose where I learned the hard way:

- center divider piece which also acts as one of the support legs is made from two pieces of 1/4" acrylic sandwiched together. It is important to glue these together first before putting into the main assembly as if they leak on the top or sides inside, it will flow through to the bottom and seep out. I found this out the hard way as this was one of my first leaks I had to seal.

- The initial pump I was going to use was a Hydor 20. Total POS in an external use application. Leaks like crazy despite manufacturers claim it can be used externally. I took this out and went to a Quiet One 2200

- Slight mismeasurment to allow for top fittings will mean a mod is necessary for my cabinet drawer to slide in and out (no biggie)

Things I did right that are important to note

- Water test first by connecting input to output with a hose but no pump. Fill with water. Dry off completely. let sit for at least two hours and then inspect for tiny leaks. Note the leaks, drain, let dry, then use #3 to fix them if any (this is how I found the issue with the center divider)

- For the top gasket - 3M pressure sensitive double sided tape (stuff with red backing) worked great. This is NOT the white foam tape. This tape works good in that it is about 1/16" thick, but will give (compress) and has a dense cell structure. (Thanks Eric - Fire Shrimp for the tip at the meeting)

- Use alot of screws (stainless) on the lid, mine has 24. One about every 1.25". This allows you to not have to crank down on the screws too much. This is important especially if you tap the acrylic for the screws.

- The reactor holds two containers of CaribSea ARM media!

- The top CO2 recirc works beautifully.

- Using tee into return pump worked beautifully (see photo below) for supply pressure

- fits beautifully in my cabinet but is a PITA to get it in and out. (thank goodness this will not be often.

Here are some photos

Pump - $40

Plumbing and fittings - $30

Screws - $5

3M tape $6

CO2 tank and regulator with bubble counter and solenoid - $115

ARM media 2 x $12 - $24

So, everything except the PH controller is $270 (this includes media and CO2 parts). This is probably half what the same would cost new, and it wouldnt fit so perfectly in my space and hold so much media and it wouldn't have been as fun or educational either.

If one has the apptitude for working with their hands, a mentor, and patience I definitely recommend it.