Received the PM1 upgrade to the Apex controller today so I can finally start up my calcium reactor. Currently running it off the apex for pH control set between 6.5-6.9 (a little higher then recommend by deltec) for now until I can judge the effects on the media, use the litermeter to feed it, and a electronic solenoid on a 20lbs CO2 tank at 2 bps.
I currently have the litermeter off for 24 hours to let the pH get to the right level in the reactor and then I'll test the effluent.
I also finished off my topoff system today. I have a "RO_Tank_High" and "RO_Tank_Low" as two float switches at the top and bottom of the 55g top off tank. The float switches tell the controller when to open and close a solenoid that is installed after the pre-filter of my RO unit. There is also a attached float switch at the RO output that will shutdown the RO system via back-pressure if the "RO_Tank_High" float valve or the RO_solenoid would happen to fail.
There is a 1.5" line between the RO tank and the Waterchange tank with a ball valve half way down it that allows me to gravity feed the waterchange tank. Right above the ball valve is a Tee fitting with a 1/2" thread output that a 1/2 to 1/4" JG fitting is attached too. There are then two solenoids in series attached to the same electrical supply in case one fails. This 1/4" line feeds into the kalk stirrer which gravity flows back to the mixing tank. The two solenoids are controller via two float switches in the sump, "Sump_High" and "Add_Water". If "Add_water" is on then the solenoids come on. If "Add_water" is off then the solenoids turn off. If "Sump_high" is on the solenoids turn off and a alarm is sound and email/text sent. The solenoids are further controller by the pH probe in the sump. If the tank pH reaches 8.4 the feed to the kalk reactor is cut off. The next step is to add another solenoid that kicks in if "Add_water" is on and the tank pH is above 8.4. This solenoid would bypass the kalk reactor and allow straight RO/DI water to top-off the tank.
If both solenoids happen to fail somehow there is only about 5 gallons that can drain from the RO tank at any one time before the siphon breaks.
If anyone sees any flaws in my reasoning please let me know. So far everything is working find. I tested all contingencies and everything works as described above. The tank pH has been between 8.28 and 8.35 for 4 days now, up from 7.94-8.2 without the kalk reactor.
