Old Kalk residue inside ATO container

coweyes298 · Nov 9, 2017

I have a 10 gallon ATO container that I used to supplement Kalk with 2 tsp to 1 gallon RODI ratio for over a year. Two months ago I stopped the Kalk dosing and using the pure RODI as ATO. But I notice there are huge layer of Kalk powder/deposit at the bottom, probably an inch thick or more. And every time I fill my RODI water into that container I get milky cloudy water.

Is there a way to check if the water has no kalk dissolved? I can confirm that I didn't see PH spike now as before when I was still dosing kalk. My PH stays 8~7.87 through out the day without adding kalk to top off water, as before with kalk top off I usually got PH 8.2 or higher value.

And is it necessary to clean the kalk deposit inside ATO container? It will be a pain to take that tall and thin container out, and it is more pain to clean it through the small opening. But the thick deposit dose look scary from outside...

saltyfilmfolks · Nov 9, 2017

I would clean it with vinegar. Probably make easy work of it.

Randy Holmes-Farley · Nov 9, 2017

I never cleaned mine. The best way to gauge limewater potency is by conductivity. Saturated limewater has a conductivity if about 10.3 mS/cm

coweyes298 · Nov 10, 2017

Well I think I found the culprit. I have high Cal reading, close to 600 ppm. I used Randy's #2 receipt 2 parts. I want to lower the Ca so I stopped Ca but still maintain ALK dosing 7 days ago. My tank ALK consumption is around 1.2 dKH per day. After 7 days doing this my ALK is stable at 8 dKH, but Ca is still 600 ppm. There is something still adding Ca into my system.

Maybe the Kalk powder is still mixing everytime I added RODI water into the ATO container. I haven't calibrated my PH probe for six months so I cannot tell if the Kalk is still mixing inside my container even I stopped dosing Kalk for 2 to 3 months. The PH probe is stable around 7.9~8.0 for the course of these 3 months.

I just cleaned the ATO container and yes there were lots of undissolved Kalk inside. I will monitor the Ca value these days to make sure there is no additional Ca adding to my system.