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watson_barrett
10/16/2009, 12:56 PM
Set-up my Ca reactor last friday. 350G system. Noticed polyp extension was poor so started doing some water testing last night.

Over the past week it appears my ALK has risen into the 14-15 range, obviously too hi.

Initial set-up, I had 120ml of effilent per minute at 6.5 ph (ARM) media.

I reduced my effulent down to like 40ml and reduced the CO2 by the same ratio. Will that help get my ALK back down into the appropriate range?

I have also been running my kalk reactor at night to replenish evaporated water.

Any thoughts?

Randy Holmes-Farley
10/16/2009, 02:20 PM
It might be adequate, but it might also still be too much. Only time will tell. You might consider just turning off the CO2 for a while until the alk drops back a bit, then restarting the flow.

I worry about "controlling" a reactor by pH, since calibration can easily drift, but the easy thing to do is add less CO2, either by raising the control pH, or otherwise controlling the flow to a lower value.

watson_barrett
10/16/2009, 05:10 PM
Thanks Randy,

How long will it take for the ALK to drop back down into a normal range, should I be testing daily or more often? Will my SPS be ok at this elevated ALK range or should i be doing a water change to mitigate the high alk levels?

Also, i'm not sure i fully understand your second comment...I thought you need to monitor PH to make sure it is at around 6.5 to dissolve the ARM? Are you saying that there are 2 methods to bring the alk back down; 1 lower flow rate of effulent, or 2 reduce CO2 output? If so, in my case where I did both will that be ok? I think you answered yes but just want to be sure.

THANKS!!!

Randy Holmes-Farley
10/16/2009, 05:33 PM
The time depends on the tank, but it may take a few days or longer in a newish tank.

.I thought you need to monitor PH to make sure it is at around 6.5 to dissolve the ARM? Are you saying that there are 2 methods to bring the alk back down

I'm saying that one way to control the CO2 addition is by pH, and another is by manual control of CO2 (bubble counting). I prefer the latter, but bear in mind I do not use a CaCO3/CO2 reactor. :D

But when you said

" and reduced the CO2 by the same ratio."

what does that mean in your case?

watson_barrett
10/16/2009, 09:05 PM
Meaning that I reduced effulent by 1/3 of output (120 to 40). I also reduced CO2 output by 1/3 (3 bubbles per second to 1 buble per second, APX). This was so I could maintain a PH of 6.5 and continue disolving the ARM media.

I guess I just woulnd't know what the PH would be without a PH probe, I would probably have a good idea after time but I'm still just getting used to it right now :rollface:

Randy Holmes-Farley
10/17/2009, 06:49 AM
Oh, it is fine to use pH as guidance. Many folks use the pH device as an on/off controller for the CO2 addition. That's what concerns me somewhat. Now I understand what you are doing and your plan is fine. :)

tegee
10/17/2009, 08:59 AM
I found the same thing happened to me when I set up my Cal. Reactor back in the spring. While maintaining calcium my alk was driving up to 12-14 range. Like you I had my ph set at 6.5 and I have always had my CO2 bubble count at 1/second (that part has never change). What I noticed is increasing the CO2 count only matter (IME) with regard to have fast it was drop your ph once it has risen in that reactor. From my experience (which is limited long term, so take it for what it is worth) is that I have raised my ph in the reactor to 6.7-6.9 to gain stability with my alk. I know some will say that I am not dissolving my arm at that high of a ph, but if I ma maintaining my calcium and also maintaing my alk who is to say that it is not working properly? I realyy do not have a technically answer for you other than it is working great at that rate.

To that end, on a 180 sps dominate tank, I have my bubble count at 60/minute and I have my ph controller set at between 6.7-6.9 depending on my alk stability.

Hope this helps

watson_barrett
10/17/2009, 10:51 AM
I found the same thing happened to me when I set up my Cal. Reactor back in the spring. While maintaining calcium my alk was driving up to 12-14 range. Like you I had my ph set at 6.5 and I have always had my CO2 bubble count at 1/second (that part has never change). What I noticed is increasing the CO2 count only matter (IME) with regard to have fast it was drop your ph once it has risen in that reactor. From my experience (which is limited long term, so take it for what it is worth) is that I have raised my ph in the reactor to 6.7-6.9 to gain stability with my alk. I know some will say that I am not dissolving my arm at that high of a ph, but if I ma maintaining my calcium and also maintaing my alk who is to say that it is not working properly? I realyy do not have a technically answer for you other than it is working great at that rate.

To that end, on a 180 sps dominate tank, I have my bubble count at 60/minute and I have my ph controller set at between 6.7-6.9 depending on my alk stability.

Hope this helps


thanks, all helpful info. So have you visibly noticed the ARM disolving with PH at 6.7-6.8? (ie less ARM in reactor over weeks/months?)

I was also wondering if the PH rises a little or "reads" a little higher outside the reactor (especially since most of us slow drip the effulent). Any studies on this? (so in other words we may be reading say 6.8 in your case outside the reactor but in the reactor the ph is in face below 6.5 allowing the media to dissolve)

Randy Holmes-Farley
10/17/2009, 11:18 AM
Some media will dissolve at even pH 7 or higher. Its all a matter of how much and how fast. :)

tegee
10/17/2009, 01:23 PM
I have not taken a reading of the effleunt outside the reactor in a couple of months, so I do not know the reading, but take one and post it here. Regarding the Arm, yes it is dissolving but very slowly. I have a dual reactor and both sides have only dropped about 1.5-2" since installation in late spring. Again, I do not claim to be an expert in tuning reactor, I just do not get caught up in all the hype at keeping it a 6.5 ph, etc inside the chambers. I simply adjust it to my tanks needs, where took several months of fine tuning and 2-Salifert Alk kits:-). Now I think I have it dialed in to where it needs to be until my sps get bigger, etc.