Approaching total coral wipe-out

[Reef Pilot]

Originally Posted by asylumdown

One of the things that I've been terrified of is that I'm not 100% confident on my alk readings. Many a moon ago when I had my first tank and I knew nothing about reef chemistry, I was stupidly using seachem reef buffer without understanding what the product was or what it really did. At the time I kept getting 'normal' alk readings for a high nutrient tank of around 9, and I dosed accordingly. What I didn't realize was that 'reef buffer' is a borate salt, which contributes to total alkalinity, but is effectively useless from a coral's point of view. I had similar SPS problems then, and when I bought the Seachem test kit that allowed you to test for borate alk vs. total alk, I discovered that my carbonate alk (the only alk corals care about) was 4.5.

As far as I know, seachem doesn't make that test kit anymore. Part of me has been wondering if the fluval brand of salt has a high percentage of borate salts in it, which has been making me think my alk is normal, as the only test kits I have access to now test total alkalinity.

With all your chemical mixing and dosing, are you sure you are ending up with the correct ionic balances?

Also, your comments re Seachem Reef Buffer are a surprise to me! I have been using that all along for my alk dosing, and the Seachem Advantage Calcium. My only complaints have been they are expensive and am looking for a replacement. But my SPS growth and colour couldn't be better.

Seachem also has/had Marine Buffer and Reef Builder, which I don't use.

And I just use Instant Ocean salt. Cheap, and seems to work well for me. I did use H2Ocean salt a long time ago (before I had SPS), but didn't like the expense.

From what you've said so far, can't say what your problem might be. Sounds almost like they are being poisoned by something. So would certainly confirm all your chemical parameters.