CA Reactor at 22 dkh?

[Wiskey]

Hello all!

I seem to remember getting 30+ DKH out of my CA reactor on my 180 many years ago, but I'm struggling to get more than 22 DKH out of the Korallin 1502. Granted my CA reactor on that tank was dual stage and much bigger but still.

I am using standard ARM media and keeping the PH (internal probe) at 6.5-6.6.

I was curious what your PH is, what media you are using, and what your output DKH is?

I'm trying to decide if I should push PH lower or if I'm going to melt the media if I do.

Whiskey

[dendrite]

I have a mrc cr1 with an added second chamber running tlf media at 6.5 ph, the recommended level, with a flow of 85 cc/min and an outflow dkh well above 35 or so. That easily keeps the 180 display and 55 sump at 8.5 dkh in a densely grown tank. Perhaps check the probe calibration, and you could always go down to 6 internally and see what happens. The worst scenario is cleaning out the mush

[jda]

I run a pretty high flow and alk at 15ish keeps my tank well fed. If could get to 20 or 25, but I would have to slow the effluent down quite a bit.

I don't test my PH... I turn the CO2 up until the top of the Korallin starts to fill with air, and then turn the CO2 down until it stops. That means no more non-dissolved CO2.

I would not got too much lower than that with the small size ARM... that is the easiest stuff to melt IME.

[Wiskey]

Originally Posted by dendrite

I have a mrc cr1 with an added second chamber running tlf media at 6.5 ph, the recommended level, with a flow of 85 cc/min and an outflow dkh well above 35 or so. That easily keeps the 180 display and 55 sump at 8.5 dkh in a densely grown tank. Perhaps check the probe calibration, and you could always go down to 6 internally and see what happens. The worst scenario is cleaning out the mush

That's a good point about calibration, I doubt it's too far off, but even 0.05 would make a big difference in this case.

Do you really think I could go down to 6.0 without melting the regular ARM media? I was under the impression that even 6.4 was kind of pushing your luck.

Thank you!
Whiskey

[Wiskey]

Originally Posted by jda

I run a pretty high flow and alk at 15ish keeps my tank well fed. If could get to 20 or 25, but I would have to slow the effluent down quite a bit.

I don't test my PH... I turn the CO2 up until the top of the Korallin starts to fill with air, and then turn the CO2 down until it stops. That means no more non-dissolved CO2.

I would not got too much lower than that with the small size ARM... that is the easiest stuff to melt IME.

I used to run mine this way, but what I found was that allot of CO2 was getting into my tank making the CO2 issues from my closed up house even worse. I was getting PH readings that topped out at 7.4 as a high in the middle of the day. I've been reading lately that this can be stressful for the fish, and impact growth rates.

That's what prompted the desire to change methods to using less effluent at as high of a KH as possible. I've added a Kalk reactor so I don't have to drive the CA reactor as hard, and I've slowed the effluant of the CA reactor to 120 drops a min about. Currently with the KH out at 22 I'm able to maintain ALK of 7.0 in the tank which equates to a ph swing of 7.7 to 8.3, but I'd ideally like to see the output at 30ish and get that KH up in the 8 range.

Whiskey

[dendrite]

I've had mine down to as low as 6.3 without any problems, but as stated , the worst that can happen is you have to clean up the reactor. When the first chamber in my reactor gets down to about half full, the tank dkh will drop from 8.5 to about 7.2 despite having ten lbs. of media in the second chamber . When the first chamber is topped up the tank dkh rises to 9, causing me to slightly dial back things . This begs the question as to whether the reactor is big enough for your system.

[jda]

Originally Posted by Wiskey

I used to run mine this way, but what I found was that allot of CO2 was getting into my tank making the CO2 issues from my closed up house even worse. I was getting PH readings that topped out at 7.4 as a high in the middle of the day. I've been reading lately that this can be stressful for the fish, and impact growth rates.

That's what prompted the desire to change methods to using less effluent at as high of a KH as possible. I've added a Kalk reactor so I don't have to drive the CA reactor as hard, and I've slowed the effluant of the CA reactor to 120 drops a min about. Currently with the KH out at 22 I'm able to maintain ALK of 7.0 in the tank which equates to a ph swing of 7.7 to 8.3, but I'd ideally like to see the output at 30ish and get that KH up in the 8 range.

Whiskey

A LONG time ago, I was talking with Dr. Holmes-Farley and he seemed to convince me that it was all the same in a well-tuned reactor. Higher output at higher PH ends up being the same as lower output at lower PH. The biggest issue with tank PH is when excess CO2 gets into the tank - the Korallin cuts down on this by design and it gets trapped in the top. A LOT of people have excess CO2 going into their tanks, which could get cut down with lower effluent rates if your system does have this issue.

This was probably over a decade ago, so my apologies if I am misremembering. In any case, I am glad that it is working for you.

[Wiskey]

Originally Posted by dendrite

I've had mine down to as low as 6.3 without any problems, but as stated , the worst that can happen is you have to clean up the reactor. When the first chamber in my reactor gets down to about half full, the tank dkh will drop from 8.5 to about 7.2 despite having ten lbs. of media in the second chamber . When the first chamber is topped up the tank dkh rises to 9, causing me to slightly dial back things . This begs the question as to whether the reactor is big enough for your system.

I was concerned about the size of this reactor, it holds about half an arm bucket and my last one held almost three buckets when empty. A second chamber might really help, i'll look into options.

I've dropped the ph to 6.4-6.5 and my kh is closer to 30 now. I've also turned up the flow through some.

Whiskey

[Wiskey]

Originally Posted by jda

A LONG time ago, I was talking with Dr. Holmes-Farley and he seemed to convince me that it was all the same in a well-tuned reactor. Higher output at higher PH ends up being the same as lower output at lower PH. The biggest issue with tank PH is when excess CO2 gets into the tank - the Korallin cuts down on this by design and it gets trapped in the top. A LOT of people have excess CO2 going into their tanks, which could get cut down with lower effluent rates if your system does have this issue.

This was probably over a decade ago, so my apologies if I am misremembering. In any case, I am glad that it is working for you.

That's interesting. I may have gone past the limits of reason in my case.

Whiskey

[dendrite]

Lol, maybe. The proof is in the pudding so to speak. If your tank dkh is somewhere between 7.5 and 8.5 and holding steady then I wouldn't worry too much about effluent. I've checked mine twice in three years, the second time after I read your post.