Mag/Calc too high? Trouble bringing down? help!

[Rskillz]

My first reef tank has been up and running for 7 months and doing quite well. The only corals I struggle to happily grow are sps, and I'm starting to think it may have to do with my mag/calc levels.

When I first started the hobby, the guy at the local LFS instructed me to dose 2 part Reef Code A&B by Brightwell once every other day, three capfuls of each (72 gallon tank) bottle. I did this for months without thinking twice, because I really trusted the guy.

Fast forward to a month ago when I decided to start testing these params with salifert kits, and my Mag was at 1500 and Calc at 500, I stopped dosing and have been waiting for this to drop with no luck. They are at 1480 and 485 now.

I guess my biggest question is what effect this will have on my tank? Any negatives besides calcium buildup on pumps? What should I do?

I use Oceanic salt, which is quite high in all levels, so maybe thats why I'm struggling to bring it down with water changes?

Any help would be appreciated!

 

[jdieck]

You are right regarding the salt. Those levels although high shall not cause a problem so just keep on waiting for them to drop. Because of the high magnesium, calcium might take a bit longer to drop.
Test your alkalinity. If I remember well Oceanic had high calcium and magnesium but relatively low alkalinity. With that calcium level try to keep an alkalinity in the 8 to 9 dKh level, if you increase it too much you might get precipitation. Once the calcium and magnesium drop you can adjust the alkalinity to the 10 dKh level.
You can temporarely make your water changes with Instant Ocean which has lower level of calcium and magnesium to speed up the process.

 

[Coral_Craig]

I don't think you should be too concerned as those levels really aren't too high. I keep my Ca at 460 and I know people bring Mag up to 1500-1600 to rid hair algae.

Water changes should bring these levels down, it just may take time (relative to the amount changed and consumed by inhabitants).

Check this site out if you haven't, it's got a lot of great info and nice chart to help you out. http://reef.diesyst.com/flashcalc/flashcalc.html