Can I use natural seawater in my aquarium?

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I live near the coast and have easy access to clean salt water for free. Are there any advantages of using natural seawater?

I wouldn’t use water from our native seas as the planktonic life within it will be coldwater/temperate as opposed to tropical, though some do. You can buy boxed natural seawater, eliminating the need for mixing and measuring.

Live seawater can be purchased, boasting added extras, including bacteria for cycling and waste reduction, and plankton for feeding corals. It does cost, however, and you have to transport it home. Yet many of us have to do that with RO barrels too!

In the short period I had 'live' seawater on test I didn’t notice any benefits over synthetic or solar evaporative make-your-own salt as I already had live rock and live sand in the tank, and they too bring in bacteria and plankton.

No major breakthroughs have been made since the introduction of live seawater and the whole hobby has been problem free with saltwater you mix yourself.

This item was first published in the August 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.