"Dialed In" ?

[RobertG]

Rock solid is right, I give the credit to the controller. It is so automated I cant believe. My tank is only growing, I top off with kalk. Other than that I dont do a darn thing. I always know when the Co2 needs to be replaced, the ph will start to shoot up on the controller. It will also never run it to much. It will shut down if the target ph is not reached in a timely manner.

I thought I needed something else for a while but now I think all is good. I have roughly 350G's.

[GaryP]

Steve,

I wouldn't worry about your alkalinity. As long as it stay consistently at that level you should be OK.

[matt]

Ca Reactor: Korallin C3002. CO2 bubble rate is about 60 bubbles/min, effluent drip rate is faster than I can count .. 3-5 drop/sec

Ca Reactor effluent: PH = 6.65-6.70, dKH = 35-40

Tank Ca = 450-475
Tank PH = 8.0 - 8.3
Tank dKH = 8.5 - 9.5

The only parameter I'm not happy with is "Tank dKH", which I would like to see in the 10-12 range, but I hesitate to push the Ca Reactor any further. Should I suppliment (something?) to get the Alk up?

I'm not sure how big or new your tank is, but I suspect that there is a lot of bio-activity that's contributing to your carbonate consumption through neutralizing acids. Another unknown is your media; I guess it's possible that different reactor media produce a different balance of calcium and carbonate ions, although I have no experiences or knowledge of this. But, let's assume you're using ARM; it sounds a little low on the dkh end, although Gary is correct, 8.5-9.5 is not a problem as long as it's stable. You might try testing water you're going to use for a water change before you do so; just mix up some water to the SG you use, and test for carbonate hardness. Might be interesting.

Also, I KNOW I read somewhere a very interesting post about the chemistry end of the interaction between calcium reactor effluent and KW. It was more complicated than one would think, and the guy basically was describing some conflicting reactions that would result in carbonate hardness dropping. I never found that post again (reefcentral about a year ago) and I never bothered to ask Randy Holmes-Farley about this idea. I suppose it's worth looking into, if you're loaded with extra time...

You might also just try the easy way out, which would be to SLOWLY add some buffer over a week or so, get your dkh up, and see what happens. Don't be surprised if your Ca drops as a result of this, but it's fine.

Wish I could be more help!

Matt

[NaCl_H2O]

Matt, thanks for the comments. I'm using Oceanic salt, and you are correct - I need to test it for carbonate hardness!

The tank/system is about 700g capacity and has been up & running since about October. I "seeded" it with LR and some sand from my 125g, but still a very immature system.

I'll check the salt mix, then think about a little buffer. A slightly higher dKH and Ca around 400-450 is where I would like to see it!

[GaryP]

I think you will find that the alkalinity of Oceanic water is pretty low. It seems like they give up alkalinity in order to jack up the calcium. Its one of the things I don't like about it. Also, I know you make up fairly large batches of water several days in advance. Alkalinity is not stable like calcium is. It can fall from just sitting there. I make up for it by adding buffer after a water change. I have to add buffer almost daily anyway. As soon as I can find another doser jug I plan to go to a constant drip system for buffer.

Also, I have heard that Oceanic is not adding some trace elements to its mixture because they feel that most people are adding them as a supplement anyway. I stopped adding trace elements because I felt that they weren't needed as long as you did regular water changes. It's a Catch-22 IMO. For these reason I'll probably switch to another salt as soon as what I am using is gone. If anyone has seen an analysis of Oceanic online I would appreciate the link. Unfortunately I recently bought a bucket.

[NaCl_H2O]

If anyone has seen an analysis of Oceanic online I would appreciate the link.

Here ya go ... enjoy :wacko
http://www.advancedaquarist.com/issu...04/feature.htm