Calcium Reactor

I re-filled for the first time the media in the calcium reactor. This time I added a little Dolomite to increase Magnesium levels as well. I never really tested low on Magnesium, so I didn't add much.

There was quite a lot of diatom / brown micro-algae growth on the inside of the calcium reactor that I also cleaned up.

Here you can see how much media has been depleted since I first setup the reactor. I've already changed out the CO2 tank twice so far. Since I always have another filled tank in stock, I can fill up the emptied tank at my leisure.

The calcium reactor is working fine. Here you can see how much media has been depleted in about three months.

I finally got the calcium reactor adjusted and its giving me 6 meq/L and 400-425 ppm calcium. I'm keeping the pH 6.60 - 6.65 and the flow rate at a steady stream (much higher than I had it previously).

Not much media has been consumed yet because I have only recently upped the flow rate.

I'm still tweaking the pH and the flowrate of the calcium reactor. I have been holding the pH between 6.73 and 6.77, producing an effluent that was testing at 7.5 meq/L alkalinity and 400ppm calcium. However, this was only keeping the tank at 4.5 meq/L and 375ppm calcium, so I have moved the pH range range to between 6.70 and 6.74. I haven't measured the flowrate, but the valve is a little more than 1/3 open.

I have just recieved and installed my new AquariumPlants.com Electronic CO2 Regulator. This regulator allows you to set a very precise bubble-rate and bubble-size, but I won't be needing that precision. The main reason I purchased it is because the manufacturer claims that this new approach will last longer than a traditional solenoid.

It makes an annoying "click" sound every time it lets a bubble through, but this sound is difficult to hear unless you are standing behind the tank. I'll see how the regulator performs in the coming days.

I discontinued the calcium reactor today temporarily. The Reef Fantatics Solenoid keeps failing and so I have ordered a whole new regulator. I was going to order just a new solenoid, but I've been advised that it is difficult to swap solenoids in and out of a regulator setup.

I purchased a Single-Chamber Calcium Reactor setup from www.reeftek.com a while back but just finally had the chance to set it up. The kit came with:

• An 18" high, ~1.5 gallon reactor with:
• An Eheim 1250 Recirculating Pump.
• A compression fitting for an in-sump pH probe.
• A Reef Fanatic CO2 Regulator with Electronic Solenoid.
• Two 5 lb. CO2 Tanks.
• A Reef Fanatic Micro-pH Controller with pH Probe.
• A Maxijet-1200 Feed Pump.
• Two 1 gallon containers of Caribsea A.R.M. coarse media.

The setup process took a little work. First I had to have the CO2 tanks filled from a "local" welding supply shop. Most welding supply shops will only swap out tanks with their pre-filled equivalents (meaning your brand new tank could be changed out with something a couple of years old) and many welding supply shops are not interested in small 5 lb. tanks. However, I managed to find a fairly professional shop a couple of miles away.

The next step was to rinse the Caribsea A.R.M. media and place it in the reactor. The media was dirtier than I expected (Caribsea's website proudly proclaims that no rinsing is neccessary).

After that I calibrated and installed the pH controller. The pH7 calibration fluid packet that came with the controller was way off, as compared to two American Marine Pinpoint pH7 packets. In fact, it's pH was around 7.5. The pH4 packet was fine though. I installed the pH probe by placing it in the compression fitting and tightening the fitting with a wrench.

Next I installed the Maxijet-1200 feed pump (I used PVC-cement to glue the vinyl tubing to the pump output so that it could handle any amount of back-pressure). I opened the air-bleed valve on the reactor and filled it with water. Then I closed the air-bleed valve and opened the reactor output valve to a few drops a minute. I also turned on the re-circulating pump.

The next day, I attached the CO2 regulator to the CO2 tank. However, I apparantly used too much teflon tape and the connection was leaky no matter how hard I tightened. I local LFS advised me that teflon tape is not for use with compression fittings. Apparantly, with compression fittings the threads themselves are not air-tight but serve only to push both pieces together and tightly squash the plastic washer in between. This washer is responsible for the air-tight seal.

Finally, I adjusted the pH controller to activate when the reactor-sump pH rises above 6.82 and stay on until the pH drops to 6.77 and I was done. Or so I thought.

Unforunately, the Reef Fanatic Solenoid on the CO2 Regulator is proving troublesome. It sometimes fails to open when current is applied and requires a light tapping to get it to open. At first it was failing more than half the time. However, I took the unit to a local LFS owner (Kevin, at All About Fish) who used a fine syringe to inject some lubricant into the solenoid. Now it fails much more rarely (somewhere around 1 in every 20 tries). However, this is still unacceptable. If this behavior does not diminish over time, I will have to replace the solenoid.

Here you can see the CO2 cylinder, the CO2 regulator, and the reactor itself.

Here you can see the pH controller.

Here you can see the CO2 reactor output tube, which I have going straight into the display tank's overflow. This is in an attempt to allow the water to be thoroughly aerated (raising the pH back up a little) before reaching the display tank. Additionally, the macro-algae in the display refugium may actually benefit from the excess CO2.