Proper calcium and alkalinity levels

[JohnL]

I've been adding a lot of acros lately and getting good growth from them. My alk has fallen from what used to be a steady 12 dKH to 9 dKH. My Ca is still 450 +.

I've been using a Ca reactor for the last two years as my only Ca/Alk replacement.

Should I be concerned about raising the Alk?

Will doing so necessarily cause the Ca to fall?

What levels do you all maintain?

[Mark]

Hey John,

I keep mine at 10 dkh, and Ca 415. That's where my tank keeps settling at, so I leave it alone. Whenever I try to manipulate it, one or the other gets out of whack. Maybe you could increase the bubbles by a couple more a minute and see what happens.

[MiNdErAsR]

I would try to bump up your alk level somewhat. With lower alkalinity levels you might lose some of the bright colors you're currently enjoying. As suggested, increasing the co2 feed a tad should do the trick.

[JohnL]

I really can't do that as I my Ca reactor (MTC ProCal) has a float valve that vents off excess CO2 and it is already at saturation. Additional CO2 just gets vented.

It's probably about time I clean the whole thing out and replace all the media in it.

[MiNdErAsR]

Then you should try increasing the effluent flow rate, then (if this doesn't help) increase co2 afterwards.

[JohnL]

I tried that Jim but the effluent Alk actually decreased. The more I think about this the more I think that float valve needs to be cleaned. :o

I'm running 40 ml/min effluent with 90 bps. Does that sound reasonable?

[MiNdErAsR]

Effluent alk decreases, but you're adding more of it to the tank. Try 50 mL/min, while leaving your bpm. I'm running 50mL/min, but I never bothered to count BPM...I go by effluent pH which is 6.70.

[JohnL]

Thanks Jim, I'll give it a try.