Jar reef

Lessons from jar reef aquariums to apply to a display tank

I enjoyed reading this month’s CORAL magazine. This issue was dedicated to jar reefing. Like the name implies, jar reefing is when you keep a reef…well…in a jar. The old-school advice always stated that you wanted a bigger aquarium because it provided advantages in terms of stability—but the popularity of these pico reefs in jars runs smack in the face of that advice.

A prior issue of Coral magazine

Here is the equipment involved in a typical reef jar:

  • Jar that is between 1 and 3 gallons in volume, with a lid
  • Small electric heater
  • Air pump, with airline tubing
  • PAR 38 LED light

And well…that’s it

  • You don’t need test kits
  • You don’t need fancy controlling equipment
  • You only feed the tank once a week

A few authors reinforced the need to be vigilant in watching the jar and taking decisive physical action to remove any threats…and generally listed water changes of 50-100%, once a week.

The key to avoiding water pollution was to feed the tank several hours before the weekly water change so that any waste would be almost immediately removed.

And well…that’s it

Why do we make our display tanks so complicated?

So why is it that we tend to make our display tanks so much more complicated? What can we learn from jar reefing that we can apply to our display tanks?

For starters—complexity, automation and having the best gear is obviously not always best.

Tight-fitting lids virtually eliminate salt creep and significantly reduce the amount of water lost to evaporation, further simplifying that chore. I do have a lid on my aquarium and my sump, but there are definitely significant portions of the tanks that are not ‘tight-fitting’ by any stretch of the phrase. If you are in the same situation, you may also want to consider the impact, here.


As long as you’re feeding them thoroughly, corals don’t need to be fed too frequently

Minimizing food waste seems to minimize problems. So, um…now I’m going to pay a little closer attention to how I feed my tank

Last, but not least, I do like the formulaic approach. The reef jar advocates all recommended some version of a precise protocol for managing the water quality, with water changes, with feeding and with vacations (dialing back the flow from the air pump when on vacation, for example, to scale back evaporation). While counter-intuitive, it sounds like a reef jar aquarium is exactly the type of thing that could help others learn the basics and get into the hobby.
I love the simple elegance and formulaic approach and am thinking about how I can make my own tank…a little more like a reef jar.


Now, off to the store to find the perfect jar for my next experiment.


Jar reefHave you ever thought about building a reef jar, or did you reed the reef jar articles in CORAL? Is there anything else you took away from that experience to apply to your display tank?






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