Precipitation Issues & Erratic Alkalinty, Calcium and Magnesium behavior

[AcanSamDC]

I have a 135 gallon system loaded with Euphyllia, Gonis, Acros, and Montis. Over the past three months I lost control of Alk/Ca/Mg and started chasing numbers and over correcting. I became aware of my actions about a month ago and struggled with exactly how to proceed. I stopped dosing for a week and my levels reacted as others suggested they would. Things are better now, but still not fully resolved.

Last night I decided to ask Claude for help. I would love to hear from someone like @Randy Holmes-Farley if Claude is giving quality advice. It was remarkable how quickly we were able to identify issues and put together a plan. Take a look! If all accurate, I learned an incredible amount in a very short amount of time.

 

[Randy Holmes-Farley Verified Community Expert]

I don't know what question you actually asked, but I'm happy to give an answer if you post it. Claude is clearly not giving desirable advice, IMO.

Claude makes many assertions in this slide show that are not accurate, and I do not recommend AI for reefing decisions. Surprising (or not) for a paid AI.


Let's start with Claude issues, in the hope people will stop using AI for reef chemistry.

Slide 2: natural salt water (assume that is what NSW means) is NOT 8.5 dKH. Closer to 6.5 dKH at typical ocean salinity.

Slide 2. Never dose alk or calcium without the other. There are processes that use or add alk and not calcium, so they may need independent corrections.

Slide 3. Root cause of precipitation:
Mg above 1400 ppm
Excess Mg² ions compete with Ca²⁺ and destabilize the Ca-Alk
equilibrium.

I have no idea what it is talking about there, but it is not true.

Slide 3 precipitation loop. I do not think that is the normal cause of precipitation. It is a simple matter of alk and pH too high, especially with bare (new) sand.

Slide 4. Claude seems to imply that kalk can overdose calcium. Never true without far sooner overdosing alkalinity, which it does not mention at all. Kalk CQANNOT flood the system with calcium. That is just nuts. Even a small calcium boost (20 ppm) is accompanied by a large alk boost (2.8 dKH) which would be a far more serious problem.

Slide 4. Claude seems to think kalk is typically controlled by a pH trigger. Not a good recommendation, IMO, and if it is, the trigger should be used as an emergency shut off not a turn on trigger.

Slide 5 is an overly complicated plan, and the 2 h recommended window (a key principle!) between alk and calcium dosing is way, way exaggerated.

Slide 6. Box 2. COs inhibits photosynthesis? No idea why it thinks that. It may be confusing cause and effect: photosynthesis raises pH.

Slide 6 Box 3 is wrong because 2 was wrong

Slide 6 box 4. Claude's obsession with calcium is dispalyed in its full glory, worrying about calcium from kalk when that is not the issue in relation to precipitation.

Slide 6 box 5 strange calcium comments like box 4.

SLide 6 Box 6/. HORRIBLE CONCLUSION: pH rising stops precipitation. It is exactly the opposite. Sad, Clade, back to school for you.

Slide 7. Faulty recovery plan since it has a misunderstanding of what drives precipitation based on its earlier misunderstandings above.