Dumb carx question

Zirky

Non-member
For todays dumb question I’d like to know if I need specific tubing for co2? Or will standard 1/4” ro tubbing due?
 
I forgot one other question. In setting the ph on an apex for reborn how much variance do I program? For example if I’m shooting for 6.5 is 6.5 off and 6.55 on ok?
 
I use regular RO tubing. The colored rigid 1/4” line.
start with PH 7.0 +/-0.2 for reborn. It will melt just fine. Start slow. Watch what the media is doing in the chamber, if it’s turning to mush, it’s too much CO2 and your PH probe is lying to you. Test the alk in the tank every 24hrs. CA is good to test too but if alk is in line, ca and Mg will follow.
 
I have a trident and a Hanna alk. I’m also dosing kalkwasser so I’m planning on setting up the carx with out turning on the co2 for a week ish and then easing into it
 
i run mine at a higher ph with a constant flow like this video

Thanks for adding this Corey, I was looking for the link earlier to post here. I too run my CaRx this way and works well. Been keeping pH in the reactor set to 7.25 and alk has been stable at 8.3 dKH for months now. I'm pulling water through my Geo reactor with a Kamoer fx-stp doser with a drip rate od 80mL per minute.
 
Thanks for adding this Corey, I was looking for the link earlier to post here. I too run my CaRx this way and works well. Been keeping pH in the reactor set to 7.25 and alk has been stable at 8.3 dKH for months now. I'm pulling water through my Geo reactor with a Kamoer fx-stp doser with a drip rate od 80mL per minute.
@BiGGiePauls33 almost running identical with the same kamora fx-stp 40mL per min
 
Thanks for sharing I watched the video, seems simple and sensible. I especially like the high flow rate. I also have the kamoa but a cheep regulator and solenoid hopefully They’ll get the job done.
 
Thanks for sharing I watched the video, seems simple and sensible. I especially like the high flow rate. I also have the kamoa but a cheep regulator and solenoid hopefully They’ll get the job done.
I went with this method after my needle valve clogged when I was away and DKh dropped to 6.5 when I got home. had some loss due to the big drop from 9 Dkh. I run the cheap millwalki solenoid nothing fancy. @BiGGiePauls33 has the fancy carbon doser style solenoid but both work just fine.
 
No need for check valve. Just loop the co2 line higher than the water line of the reactor. I find CO2 check valves are prone to failing. I don’t run one in my set up.
 
Cool, thanks nick I’ve got it running without co2 now. Perhaps I’ll start dosing co2 tonight
 
Hi, I am new to CaRX. I got a geo612 with arm coarse media. My 160 gal sps heavy reef consumes 1.5 dKH per day. Over four days I have titrated the CaRX pH down to pH 5.9 and 50 ml/min delivered by versa pump, I can keep up with alk consumption over 24 hours but I see a 1 DkH diurnal swing which I had flattened out much more when using 2 part previously (see attached trident data; CaRX came online 12/23). I set the bpm at 90 using milwaukee regulator and the CO2 solenoid mostly stays on. I am only seeing 20dKH in the effluent at the 50 ml/min. I hesitate to use the reborn reformulated media due to pictures online of the cigarette butts, glass, and astropod shell contamination. I ordered a 2 gallon secondary chamber SMC618 from GEO but it will take a month to get here. I am wondering your guys experience with a 1 dKh diurnal swing and whether this is a problem for the corals. Anecdotally, I think I am seeing less polyp extension but I am a biased observer. I am able to completely stabilize tank pH at 8.2-8.4 dirunal swing with Kalk reactor no problem (see attached pH data, kalk reactor was brought online 12/24). So excess CO2 in the effluent is adequately converted to bicarbonate by the Kalk.
 

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First off. 90bpm(bubble per minute??) is crazy.
Secondly 1dkh is totally can be in the tolerance of the test kit.
The PH swing is fine given your probe is properly calibrated.
To me, if I test the tank and alk is 8-10dkh, ca400-450ppm, and Mg is 1200-1400ppm, I usually leave it alone.
Yes, reborn is a bit nasty. Takes some work to rinse it off and sometime pick through the media.
 
I agree 90 bpm is crazy. Having to set the pH to 5.9 to generate alk to match the consumption rate is not reasonable. The media just does not melt fast enough to keep up with the consumption rate during the day setting up the 1 dKh diurnal swing. If the error in measurement of the trident was 1 dKh, I would be surprised to see the continuous curve in the original post. Wouldn't I expect to see random oscillation with a 1 dKh amplitude. So if the Alk measurements are accurate, I think you are saying that a 1 dKh diurnal swing within 8-10 is fine. Is it correct?
 
I think your carx might not be big enough for the tank. ARM media has a melting point of around 7.0PH. Is the media turning to mush at the bottom?
Sorry, I don’t know how a trident work. Does it monitor alk through a probe continuously or is it just an automated alk tester that does the test for you based on your setting. If it’s a probe, there shouldn’t be any tolerance from one reading to next. If it’s automated test, I would still expect the tolerance between tests.
CARX can be a headache if you chase the numbers. If your corals look well and the media is not turned to mush, I wouldn’t sweat it. PH can be a silly number to chase especially if you don’t have a good quality probe and is calibrated often.
 
So far it has not turned to mush. It seems that the production is increasing slowly over time at this low pH. Perhaps it just takes a few days for it to rev up. the goal of controlling the PH was to just create stability with the excess CO2, so I set up a 8.2 to 8.4 diurnal swing and maintain this stably using the kalk reactor. I have some reborn coming from Marine and reef. Supposedly they have the large chunks now. I actually had the customer rep check the shelves to make sure it actually is the larger pieces. I will let you guys know if this is truly the large chunks when it comes in as I understand that only the "little" has been available recently. Trident is reagent based with an advertised accuracy of +/- 0.05 dKh. Are there probe based alk tests? I think they are either titration based (KH guardian/alkatronic/KH carer/KH director) or reagent based (trident).
 
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