Hey, what do your Ca and Mg levels actually test at with RO/DI + Tropic Marine Pro?

Thanks everyone!

It turns out that an Aqua-Safe RO-DI system isn't as expensive as I thought. They sell them on eBay for $85 US including shipping. Compare that to $45 for the Aquarium Pharmaceuticals tap water filter and the choice seems obvious.

I would like to understand the differences in the salt mixes. Instant Ocean doesn't say too much about theirs. Kent and Seachem both talk about enhanced levels, i.e. greater than found in natural seawater, which puzzles me. Is this a good thing? It appears that Tropic Marin simply replicates natural seawater which sort of makes sense to me, keeping in mind of course, that I've never had a reef tank.

"Kent Sea Salt contains enhanced buffer levels and enhanced levels of important minerals, such as calcium, strontium, iodine, iron, cobalt, rubidium, lithium and many others."

"Seachem's Reef Salt will support and promote enhanced calcium and alkalinity stability for those wishing to maintain calcium above Natural Sea Water (NSW) levels (400 mg/L) as well as providing NSW levels of bromide (65 mg/L)."

"Tropic Marin Sea Salt contains all 70 trace elements in the natural concentrations of the ocean. No more, no less."

I agree with what's been said above about the RO/DI water saving you from a lot of algae problems. I started with that 1 1/2 years ago and have never had hair algae in my tank.
On the topic of salt, I started with IO but determined it was really messing with my numbers. After looking at a lot of the forums on RC and others, I have gone with Marine Environment salt...really awesome stuff! Gotta get it only from Aquarium illusions in Edmonton though as they have exclusivity in Western Canada. They ship Greyhound and are excellent to work with.
Just my 2 cents.

welcome aboard dcmoore;

As you are probably noticing after reading all the posts, there is a lot of difference in opinion regarding most aspects of this hobby which adds to its fascination. You would think that simulating natural sea water would be the best for your SW tank. However, we have small closed systems which results in rapid depletion of several minerals and trace elements in the water. Therefore, it may be better to increase the dose of calcium, magnesium etc. so the levels don't fall below physiological levels too quickly. However, if you have a fish only system then probably cheaper salt like IO may be perfect for you. However, if you are planning on having a reef tank then I would start with a more expensive salt that has higher levels of Ca and Mg which means you have to spend less to supplement these. Pick one brand of salt that is easily available and stick with it (if you are happy with it). This is good for consistency and will let you become familiar with the characteristics of that brand of salt. Regular water changes are also important to keep the mineral and trace element levels in the appropriate ranges.

Happy reefing,
Shane