Alk Cal & Mag Testing.

[AJreefs]

I have been told consistently that preventing swings in parameters in a tank is really important. This makes me wonder, with test kits only being accurate within a specific range(e.g. half a DKH for ALK) how are you more experienced reefers ensuring you arent experiencing swings?

 

[KJAG]

While any kit is probably not 100% accurate, its close enough to find a baseline and prevent swings.

 

[AJreefs]

I felt I was missing a component since theoretically the kit could place you off 1dkh due to variations within the tests. It was my understanding that a DKH swing of 1 is unacceptable for an sps tank. Which brings me back to my question that if the .5 variance can be + or - .5; thats a possible 1 dkh variation between tests. Thanks for the response.

 

[mcarroll]

Well, there's consistency and then there's consistency, right?

Nothing is 100% consistent - not even the ocean. Regardless of advice that might be a little too specific for its own good, what you want not to do on any tank with fast growing stony corals is do anything less than daily dosing.

Many people want to be cheap, lazy, or both when it comes to stonies and this amounts to slack water changes and weekly (or worse) dosing. Ultimately this will end badly. (Which I have never understood - they never have a problem getting into a daily routine to feed fish.)

You can get by with no or very little dosing when you start out, but past a certain point you will have to be locked in on this - either with a daily routine or (much recommended) some kind of doser that will allow you a weekly refill routine.

Also, something to remember about test kits: the key to their use is consistency. Consistency allows the uncertainty to be factored out. You're not so concerned whether the number your kit gives you is accurate (tho it would be nice), you're more concerned that you can use that number to gauge (and rectify) changes. The question (thankfully) is not "is my alkalinity 4 meq/L?" but instead "how many points has my alk dropped?" Most kits these days (Salifert being my fav) are more than accurate enough to serve this purpose.

-Matt