Alkalinity confession - and question

[X-37B]

My systems have drooped to below 6dkh a few times with no issues.
Average ocean alk is 6.5. I run my systems at 7-7.5.
I would bring it up to 7 and use a 2 part to keep it there.
Get 2 kamoer pumps to dose ca and alk. I use esv 2 part on 3 systems, carx on main.

 

[IntrinsicReef]

I do remember reading that, and remember the tank was very nice as well. I have also read/seen calcium carbonate structures beginning to "dissolve" below 6.5dkh. I am not a chemist and dont really know how to quantify this I'm sure ph needs to be a factor like in a calcium reactor. My guess is that if it actually was 5.5 growth would probably just stagnate. But since there is mention of a doser which most likely means there is something alk related being dosed and there for the test is off.

I am going to leave all that I typed above....I'm not infallible and I really dont have a great chemistry back ground. I am at work and I deal with techs all day wanting parts, so I have to stop typing things in the forums and then come back and reread what I typed and finish or make changes...sometime takes me 3 hrs to post something like this. lol I started to reply at 9:45 and its now 10:43 lol

I guess if you calculated you need to dose .5dkh/day 6 months ago and stuff grew and now needed 1.5dkh/day that would easily explain the 5.5dkh now if you are still dosing at the .5dkh need. I am getting myself in the weeds here. Just cross check you tests, probably wouldnt hurt to get new reagents as well. If you need to adjust the alk go slow its easy to do. Interested to see how this turns out.

Yes, @Randy Holmes-Farley did say that pH was a factor in the equation with dkh where calcium carbonate started dissolving. I ran some tests on that tank and I think we concluded that low alk was the limiting factor in coral growth. The corals seem to grow when it gets above a threshold ( water changes in that instance), then stop growing when it is depleted to a certain level. It seems to be around that 5.5 dkh range.

 

[Jimbo327]

Definitely double check your water with the LFS or another reefer's test kit.

 

[NigelRichardson]

The plot thickens.... Alk definitely 5.5 - Double checked (or more!) with LFS Hanna Checker and 2 x Red Sea Test Kits...

Working to raise Alk super super slowly (0.2 / day), but still surprised to learn that I may have defied the laws of chemistry and biology by having Alk go that low and everything still looks ok...

Not a "flex" - more of a "I can't believe I got away with it" !