More helpful if you mention what salt :razz:

LOL, Sorry, I thought the conversation was about the regular IO salt. :)

Fair enough :) 330 is more in line with what I would expect from IO..

Sorry Shelley for all the Hijacking

I've just mixed some IO NSW and will test it tomorrow
I'll grab a couple Seachem kits while I'm out to compare to my Elos ones
I'm not going to waste money on the Seachem Mg kit though ... at least not at this point :wink:
Even though it's not the point of your thread, I'll report here for anyone who's curious

So, I know it hurts you to do big ones but, are you going to do a WC to get your tank back inline ?

No worries about hijacking. It is all relevant.

I got a five gallon water change done today, and I've got another one prepped for tomorrow. The boys (hubby and #1 son) will be around tomorrow, so they can lug the water up the stairs for me. :) Trying to get the water upstairs is pure evil on my knees.

I'm just about to go test ca/Alk/mag.

Ca 300/alk 9.52/mag 1375

I am NOT going nuts! This system tested 350 for calcium 10 hours ago. I must have a calcium sink. I have some really good growers in here, but the growth from my plating monti is really significant. My Hollywood stunner and green birdsnest are two other fast growers.

Could my system really be using up that much calcium in a few hours?

I just tested against the known sample again. The test checks out.

No. My system doesn't even use that in 10 hours, and I've got a lot of coral growth.

im also going to say no , so bring a water sample over here and lets test it against mine. bring your test kit and we will use both yors and mine if you like:)

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?

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...