Ca/Alk/Mag Mess . . . How to fix?

[gregzz4]

And after posting, I see some good advice from Dan too

Best if you up one @ a time so you can monitor it alone and it's affects ...

[Lampshade]

Before you do anything, is coral OK? i recently nuked my tank because my alk test said 6dkh and calcium said 420. Be VERY careful with your tests, i took an API and a salifert beside each other with one saying 6-7dkh, the other 17dkh.

Basically what i'm saying is before you do ANY corrective actions, first make sure you actually need the correction, and if you do, get a second opinion. I lost $1500 worth of SPS because i cheaped out on a test kit then trusted it, don't do the same :P.

[FragIt Dan]

If I were to take a guess, the reason why your dKh is dropping when you add Ca is because your inhabitants are finally getting the Ca they need to consume the carbonates. With Ca that low, I pretty much guarantee it is not precipitating out with the dKh, so that suggests your dKh is being consumed along with the Ca as soon as you are adding the Ca. I would increase your Ca and dKh dose until you see your Ca increasing and your dKh steady. Dose one when you wake up, the other when you go to bed. You may be surprised how much of these your tank goes through when it has good levels. I started dosing at 20ml dKh and had it up to 200ml/day before I could get it to stay level above 8.
Dan

[FragIt Dan]

Originally Posted by Enigma

Ugh. That was not the response I wanted. How about five gallons a day? 55 gallon system.

I'm worried about shocking the livestock.

I think you need to balance shocking the livestock with a 50% water change against the stress a 300ppm Ca level is putting on them. I have had my tank almost that low at times and lost corals because of it. +1 on Aquatro's comments... get the Ca up quick.

[FragIt Dan]

I think you should be consuming 2.8 degrees dKh for every 20ppm of Ca. I don't know what is going on with your Ca, but something doesn't add up. I am going through about 20grams anhydrous CaCl or about 20-30 ppm Ca in a heavily coral loaded 90G tank (twv of ~100G) per day. 50ppm in 10 hrs and with levels that low... IMO neither your corals nor precipitating Ca would account for that. Perhaps you could calculate how much you expect your Ca to raise based on how much Ca you are adding and your tank volume. You can calculate how much it should go down based on your dKh consumption. Test results that vary from this might need to be double checked?

[Aquattro]

Quick question for those with really high levels of Ca...what are you using to test salinity? Is it accurate?
My Ca was up around 500 in an old tank for a long time. I was using a swing arm hydrometer that went south and my salt was at 1.036 for months. Ca was way high....just a thought...

[Aquattro]

Tested my Ca for fun, 450ppm. I can live with that..

[Enigma]

Originally Posted by Aquattro

Tested my Ca for fun, 450ppm. I can live with that..

Show off.

Edit: I'm picking up the Elos test after work . . . AND the hanna checker. This is going to drive me nuts.

[Aquattro]

i expected a value near there, i run a good sized Ca Reactor. And the Reefers Best salt is about 420 out of the box.

[FragIt Dan]

Originally Posted by Enigma

I also picked up Aquavitro 8.4, in the event Alk crashes (this will raise pH and Alk). According to the Calcificatin bottle, 8.4 can be dosed within minutes of calcification. Curious. I'd like to try it to see what happens, but that is kind of scary.

Hah, I bet it's just pure bicarbonate (baking soda) with no carbonate. This would pH balance it a bit lower and prevent the Ca from precipitating out. I am curious if, when you add it, do you get the typical milky response in the water as when you add the normal Alk supplement? My theory is that you don't. I am guessing you just bought the same as Arm and Hammer from a grocery store, but that's just a guess. Incidentally, that is what I dose for Alk, with a bit of Carbonate to pH balance it a bit the other way.
Dan