Whats going on with my alkalinity?

[Bug_Power]

What about phosphates and heavy metals? I would be scared to use anything other that RO-DI unless you know exactly what is in your water. Get that RO-DI system, actually what kind of tank do you have? I mean SPS, LPS fish-only, etc?

Phospates = 0, Nitrates 0 We checked for metals and found none. I was really surprised. However my water comes from the ground water about 500 feet from the lake. I was concerned until we tested it and it came out ok. I'm going to go ahead and setup a RO-DI system at the other house.

BTW what's the difference between Ro and RO-DI. Is the deionization really that important?

[GaryP]

DI basically acts as a polisher to remove anything that sneaks through the RO membrane.

[GaryP]

OK Discuspro, not really to make your life difficult, but basically because I don't have anyone else around here to have this discussion with; how about non-photosynthetic corals, such as Dendronephthya or Nephthyigorgia? They still use calcification to build calcium carbonate spicules don't they? How does photosynthesis fit into your model in that case? I really didn't plan on turning this into a Master's oral defense, but that is the kind of questions you could expect.

In all honesty, and that was my original point, we are talking about two seperate but related mechanisms. You are looking at it from the standpoint of an overall net mass balance, and that is fine. My point was that calcification and photosynthesis are seperate biochemical mechanisms that a zoanthellae containing coral contains. The role of CO2 and/or carbonate are both important of course. Mostly it's just a matter of intellectual hair splitting. But I just love splitting hairs. I understand the biochemisty of sugar production and phosphorylation and all that. Just don't ask me to recite the Kreb's cycle from memory. I've slept several thousand times since the last time I looked at it. I used to do research on developing bio assays based on quantifying ATP with luciferase for industrial applications. I even wrote papers on it for a couple of journals that are so obscure that you would never find them in a million years.

You should see the glassy eyes in the room when I try to bring up stuff like this in a MAAST meeting talks. I usually stop as soon as I start to hear snoring. Maybe we can get bstreep to jump in here. He used to be a biochemist. Then we can have this thread all to ourselves, because everyone else will be asking themselves "what the heck are they talking about?"

[GaryP]

BTW, I checked at Barnes and Noble and they just ran out of the latest edition of Limnology and Oceanography. Darn my luck.

[discuspro]

That whole model is not my idea but McConnaughey's. I'm just trying to make sense of it, I've found what I believe are loop holes in it as well. McConnaughey was making that model only for photosynthesizing calcifyers and since that is the bulk of the stock in my tank that is why I've applied it to try and figure out why my alkalinity was dropping more that I was expecting.

Before I put words into McConnaughey's mouth I need to read this one again. I don't know if it'll be copyright infringement but I could email you a copy of that journal article. I get it through the account that St. Ed's U has.

Last night I was also thinking why would a second bicarbonate need to be broken down when the CO2 that would be needed could be supplied with the surrounding CO2 in the water? Maybe it would be more energetically stable for a bicarbonate to split into water and carbon dioxide? Like I said I need to read it again to get it fresh in my mind but I can't remember if McConnaughey et al. proved this by experiment or not.

[GaryP]

OK, think about this. Terrestial plants photosynthesize too, right? How much bicarbonate is present in the air? None? That doesn't mean that it may not be converted into bicarb in the plant tissues though, so you have me on that one. As a matter of fact it would just about have to be mostly converted to bicarb in the intercellular pH. Where is a botanist when we need one?

The thing is that CO2 is going to be fairly rare at the pHs we are talking about. You need to look at the pkH for CO2 and bicarb.