Reactor Affluent PH Question

[thysrof]

just changed the Calcium Reactor media and the affluent is running 7.15 PH,the tanks runnig 8.2ish. Isn't that a little high of a PH for the affluent?

 

[jkreefer]

yes i belive so. what kind of media are you using

 

[burris]

changing the media may have increased the flow through the reactor which will raise the effluent pH if the CO2 injection rate has remained constant

 

[northbay-reefer]

you want to run about 6.7 inside the chamber so increase the bubble count slightly or slow down your drip rate. But while you are making these adjustment, keep a close eye on the alk of your tank. because as the ph lowered and co2 increases in your chamber the alk of your tank will start to go up. So make very small adjustment and wait 24 hours, measure everything before making anymore adjustment.

 

[thysrof]

Will Do,Jeff I'm using ARM's small media. I think I'll start using a larger media. The ARM started to brakedown a little too quick.

 

[northbay-reefer]

Bob, yeah the small media is good, but the bigger ones are better. The big media you can buy in bulk alot cheaper

 

[corndogg]

6.7 is perfect for A.R.M.

I prefer 6.5 for the coarser media like shuran or gen-x

Have you tested the alkalinity of the effluent coming out of the reactor?

How are you testing the pH? Test kit or pH monitor.

 

[thysrof]

I'll test the alk of the affluent from the reactor. What level of alk are you shooting for?

 

[corndogg]

The higher the better. Means your using the co2 more efficiently. Depending on the reactor, you shoot target a dkh of 40+

This calculator will show you how much to adjust effluent and co2 according the the test results. http://home.comcast.net/~jdieck1/reactor.html

 

[thysrof]

Jason,
Thanks for the link to Reactor Calculator,I didn't know there was such a tool.

Bob

 

[jdieck]

Use section 2 of the calculator to estimate your adjustments.
A couple of tps:
The lowest the effluent flow required to maintain your tank alkalinity without being lower than 25 ml/min the less impact the reactor will have in the tank PH.
Try to keep an effluent Ph above 6.5 for small media.
Small media is my favorite for downflow reactors given its dissolution at a higher PH and increased exposed area. You do not need to replace the whole media, if it starts gettign muddy just take it out, rinse it in a bucket to remove the small particles and place it back in the reactor and top it off with new media, trow away the first water that pases thru to get rid of residual tap water carried with the wet cleaned media.
Do not get hung on the alkalinity of the effluent, whatever it is is OK as far as it maintains a constant alkalinity in your tank.
Do manual adjustments of Calcium as required in case it becomes out of balance.