cal/alk/dhk .. in trouble!

[3mrhythm]

okay i've used the salifert calcim test kit and got a high reading on the calcium

here is my question .. for those familiar with the kit


they have a 1ml syringe for the reading based on what is left in the syringe you can calculate the calciums ppm

so if you use .2ml you have .8 left and it calculates as follows

ppm ca= (1-reading)x500

so if i used all the of the syringe i would have (1-0)500 which would give me a reading of 500ppm

i had to use 1 full syring so 1.00 and anoher .2ml so if i have a negative figure meaning more than one syringe which way would it go?

(1-(-.8))500 ? so 1.8x500 which would equal 900ppm

or would it be 1-(-.2) since i used .2 extra? which would leave me reading at 600 which sits a little easier .. still much .. but not as scary


Other Readings:
alk is 2.29
dKH is 6.4

either way im in a hot zone calcium wise.. whats the best way to get it down?

[Dave]

>would it be 1-(-.2) since i used .2 extra? which would leave me reading at 600 <
That is how I would interpret it. If you want use the low resolution test and double the result. Should give you the same result (600).

[3mrhythm]

i'll try that .. 900 is scary .. makes since since it would be -2 if the syring went ended at 0 and went to -.2 on the syringe :)

so 600 isnt that bad.. enough of the coralline up stuff :)



so the question now... is it safe to drive the alk up? with out risking the calcium falling out of solution?

[chew*]

If you drive the alk up you may end up with a snow storm, I would ride it out a week retest then try to very slowly bring alk up.

consequently if your alk is low so is your PH.

[3mrhythm]

i have plenty of kent superbuffer dhk here and a bottle of the alk part of the two little fishes c-ballance

which is safer to use?

[chew*]

No clue never used either. I drip kalk, and use B-ionic by esv to correct any inbalances.

[3mrhythm]

ph is at 8

[3mrhythm]

http://www.reefkeeping.com/issues/2002-04/rhf/feature/index.php

according to that should my alk be at 12?

[MikeG]

Your calcium is at 600 based on your test results as others have said. If you want to get things a little more balanced and bring the alk up, I would just do a water change. That will increase alk and bring down calcium.

[3mrhythm]

i guess i'll get changing :) figured i would probably do that ..safer than playing mad chemist :)

[chew*]

the biggest mistake you can make is trying to fix something with chemicals, gradually letting it fall is safest. Waterchange would not hurt, adding alk could and would. Alk swings can be far more devastating than any other chemistry in a reef tank, especially with sps.

[jimmyj7090]

BAD SALIFERT KITS ARE OUT THERE!!!!


Please reality check those numbers before doing anything else.

IME salifert was usually very reliable. Sometime, I think earlier this year, they put out at least one bad batch that consistently reads way high - like 425 real level testing at 550-600.

The exp date on the bad Kit I got was 12-2011 (yellow sticker on top of the box. The bottles are marked as follows;
Ca-1 batch:1106-F
Ca-2 batch:1106-H
Ca-3 batch:1106-C


Here's a link to my thread with almost the exact same problem your having. See post #16 (page 4) for where it all came together.

[3mrhythm]

expiration date on mine is 2009..i'll take some water to work and test it

[jimmyj7090]

Yes, please do. My exp may have nothing to do with yours, but it can't hurt to rule it out.

jk

[Dragon2115]

You can also mix up a small quantity of salt water to use as a test standard. If you test newly made salt water and it's testing at 600 ppm CA then you know your test kit is off. IIRC, Instant Ocean (when mixed to 1.025 SG) was 380 ppm and IO Reef Crystals tested out at 450.

[jimmyj7090]

That's a great point, (reality check by testing fresh pre-mix) it would not necessarily be accurate at all, but if fresh mixed IO tested at 499 Ca you'd know the test is off.

FWIW, IME I've tested fresh IO mix at roughly that salinity as low as 330 ish with a salifert kit (that appeared to be from a "good" batch). Still, we all know that fresh IO won't be high in Ca by reef standards so if you tested it and it read well above 450 it would be pretty obvious that the test was off.

[Dragon2115]

Absolutely. I should have said that those numbers are only approximate values.

[bbjohngm]

Maybe I'm just paranoid lol but when I do tests I always do more than one for the same test ie. I use both Salifert and Elos tests ...sometimes I'll even do a third with the AP test kits I have...that way if the numbers are drastically different I know either it's me that messed up or one of the test kits is messed up....I may be over doing it some, but the way I see it, I only test once or twice a month so why not just make sure it's done right!