Steve2020
Well-Known Member
There seems to be a lot of post's lately about ph, CO2 scrubbers and skimmer recirc setups so I decided to collect some ph data for different scenarios. The data emphasizes more towards tends and not so much the actual ph values.
My tank and parameters: LPS and Softies. 285gal total water volume which includes a 30gal external refugium with reverse lighting I just restarted a month ago not so much for ph stabilization at night but for nutrient control. I auto dose BRS 2 part at 85ml/day dosing every 2hr. 8pm-6am 5ml every 2hrs except for 10pm which I do not dose because I occasionally dose MB7 at 8:15pm and turn of my return pump for 3.5hrs, from 8am-6pm 10ml every 2hrs. 170ml of Tropic Marine Balling part "C" daily. I also dose live Phyto every night. 4gal AWC every 4 days equates to approx 10%/month water change. 1.5ml Red Sea Colors daily.
NO3=12.1 dropping 1.6ppm/wk, was at 18.2 before refugium.
PO4=0.06 dosing trisodium phosphate solution to keep fairly stable. Was at 0.18 before refugium.
Alk=9.0 very stable
Cal=445 very stable
Mag=1510 very stable
Salinity=34.9-35.0
Temp=77.5-78.2 controller controlled
House and tank location: House is fairly new, 2485sqft and well sealed for the Minnesota winters. Tank is located in the lower level with windows and a walkout sliding door that are open when the weather is good which is not many days a year unfortunately.
Tank equipment: 4 GHL Mitras 7206's running a 12hr schedule with a 3hr ramp up and down time. 6hrs at full spectrum. 2 MP60's and 2 MP40's with custom made adjustable deflectors pointed in a upward direction which gives me massive amounts of surface agitation. One thing about the surface agitation is I get very good gas exchange which is probably good and bad. Good for increased O2 but bad for increased CO2 when house is sealed up. Skimmer is a Reef Octopus 220-INT Super Cone that has the capability of pulling in 2400L of air at max setting. I only run the controller in position 3 out of 5. BRS Duo Jumbo CO2 scrubber setup as a full recirc with an outside air input into the scrubber and a electronic ball valve to control the ph which is programmed by the GHL Profilux Controller. Electronic ball valve is programmed to open at a ph of 8.38 to allow CO2 enriched air into the skimmer and to close at a ph of 8.36.
The ph scenarios I tested are:1. Running full recirc with outside air input into scrubber. 2. Full recirc with outside air to the scrubber and windows and sliding door open. 3. Windows and sliding door open only with scrubber bypassed and scrubber output hose removed from the skimmer air input. 4. Outside air to the scrubber with no skimmer recirc.
The below screenshot shows that when the windows are open and in full recirc that you get the biggest kick in ph. Unfortunately the electronic ball valve even though open, the ph goes beyond my desired setpoint by .11. Most would say hey that's a good ph but when I used to run my upper setpoint at 8.45 before I lowered it I got some pretty bad calcification of my shallow sand bed. I am not saying it was the only factor but I do believe it was a contributing factor after reading some of Randy's writeups . I have redone my sand bed since then and all is good so far. The full recirc is what I primarily run and it also has the outside air input into the scrubber. Works great for what I want and the ball valve keeps it from going above my current setpoint of 8.38. The outside air to the scrubber only test surprised me a little. I was expecting a higher ph more inline with the full recirc. I believe that having the house sealed in this mode that the surface agitation is adding a decent amount of CO2 to the tank water. Not very efficient IMO. The full recirc configuration with outside air input even with a sealed house performs much better than the outside air only to the scrubber.
The little downward spikes you see are when I dose Phyto and go into feed mode which shuts down the return pump and skimmer.
This screenshot shows the difference between windows open with full recirc and windows open with no recirc.
Just thought I would add this so you can see the data point from yesterday and where it is at so far today. This is a full recirc with outside air input into the scrubber.
Skimmer recirc and outside air input into scrubber.
Skimmer recirc airlines. I removed these and the air input to the skimmer when doing the windows open only test.
Fresh air from outside. Furnace fresh air supply. Hose runs 60ft to the scrubber.
Fresh outside air airline coming down from lower level celling crawl space to the scrubber.
Electronic ball valve.
CO2 color changing absorbing media I use.
My tank and parameters: LPS and Softies. 285gal total water volume which includes a 30gal external refugium with reverse lighting I just restarted a month ago not so much for ph stabilization at night but for nutrient control. I auto dose BRS 2 part at 85ml/day dosing every 2hr. 8pm-6am 5ml every 2hrs except for 10pm which I do not dose because I occasionally dose MB7 at 8:15pm and turn of my return pump for 3.5hrs, from 8am-6pm 10ml every 2hrs. 170ml of Tropic Marine Balling part "C" daily. I also dose live Phyto every night. 4gal AWC every 4 days equates to approx 10%/month water change. 1.5ml Red Sea Colors daily.
NO3=12.1 dropping 1.6ppm/wk, was at 18.2 before refugium.
PO4=0.06 dosing trisodium phosphate solution to keep fairly stable. Was at 0.18 before refugium.
Alk=9.0 very stable
Cal=445 very stable
Mag=1510 very stable
Salinity=34.9-35.0
Temp=77.5-78.2 controller controlled
House and tank location: House is fairly new, 2485sqft and well sealed for the Minnesota winters. Tank is located in the lower level with windows and a walkout sliding door that are open when the weather is good which is not many days a year unfortunately.
Tank equipment: 4 GHL Mitras 7206's running a 12hr schedule with a 3hr ramp up and down time. 6hrs at full spectrum. 2 MP60's and 2 MP40's with custom made adjustable deflectors pointed in a upward direction which gives me massive amounts of surface agitation. One thing about the surface agitation is I get very good gas exchange which is probably good and bad. Good for increased O2 but bad for increased CO2 when house is sealed up. Skimmer is a Reef Octopus 220-INT Super Cone that has the capability of pulling in 2400L of air at max setting. I only run the controller in position 3 out of 5. BRS Duo Jumbo CO2 scrubber setup as a full recirc with an outside air input into the scrubber and a electronic ball valve to control the ph which is programmed by the GHL Profilux Controller. Electronic ball valve is programmed to open at a ph of 8.38 to allow CO2 enriched air into the skimmer and to close at a ph of 8.36.
The ph scenarios I tested are:1. Running full recirc with outside air input into scrubber. 2. Full recirc with outside air to the scrubber and windows and sliding door open. 3. Windows and sliding door open only with scrubber bypassed and scrubber output hose removed from the skimmer air input. 4. Outside air to the scrubber with no skimmer recirc.
The below screenshot shows that when the windows are open and in full recirc that you get the biggest kick in ph. Unfortunately the electronic ball valve even though open, the ph goes beyond my desired setpoint by .11. Most would say hey that's a good ph but when I used to run my upper setpoint at 8.45 before I lowered it I got some pretty bad calcification of my shallow sand bed. I am not saying it was the only factor but I do believe it was a contributing factor after reading some of Randy's writeups . I have redone my sand bed since then and all is good so far. The full recirc is what I primarily run and it also has the outside air input into the scrubber. Works great for what I want and the ball valve keeps it from going above my current setpoint of 8.38. The outside air to the scrubber only test surprised me a little. I was expecting a higher ph more inline with the full recirc. I believe that having the house sealed in this mode that the surface agitation is adding a decent amount of CO2 to the tank water. Not very efficient IMO. The full recirc configuration with outside air input even with a sealed house performs much better than the outside air only to the scrubber.
The little downward spikes you see are when I dose Phyto and go into feed mode which shuts down the return pump and skimmer.
This screenshot shows the difference between windows open with full recirc and windows open with no recirc.
Just thought I would add this so you can see the data point from yesterday and where it is at so far today. This is a full recirc with outside air input into the scrubber.
Skimmer recirc and outside air input into scrubber.
Skimmer recirc airlines. I removed these and the air input to the skimmer when doing the windows open only test.
Fresh air from outside. Furnace fresh air supply. Hose runs 60ft to the scrubber.
Fresh outside air airline coming down from lower level celling crawl space to the scrubber.
Electronic ball valve.
CO2 color changing absorbing media I use.
