Choong,
You have a point there, the algae problem is also my first concern. Using your method, even the water has no contact with the inner tank, I think algae will still develop if the light source is strong enough, I think it's just a matter of time before you have to add filter and/or start scraping the glass walls...
Algae will develop no matter what, provided there's a bright light source (unless the water is sterile and have no contact with air), I also got some experience from planted tank before.
Since we're discussing this topic, how about using a mini bar fridge to cool the terrarium? Electric bill will probabaly not be too expensive or will it?
Ken & Edward,
The cooler box method will work for short term, but can you guys keep on doing this for years to come?? Day after day? What would you do when the collectons and plants got bigger?
So soonner or later, if you plan to grow HL neps, you'll need a chilled terrarium...
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