Ever since I got seriously into this hobby 9 months ago, I've seen flames and praise about Diana Walstad's book about a "method" of having naturally planted tanks using capped soil, with "no filtration" and infrequent water changes. I found this amazing article while researching these natural planted tanks. I'm not sold on successfully keeping shrimp in a 1g bowl, but the idea of a tiny ecosystem intrigued me.
Basically, moistened organic potting soil is layered on the bottom of your container along with any additional fertilizers you may wish to add (I used Osmocote - thanks Cobfreak for the tip), 1" thick. It's recommended to place a border of small-grained gravel or sand prior to planting. Set your plants into the soil and then cover all soil with up to 1" of your gravel/sand. Slowly (Did I mention, slowly?) fill with dechlorinated water.
Ms. Walstad uses lots of sunlight for her bowls, but I don't have that kind of placement available - so I'm using a 15w daylight bulb.
This is the 2nd Walstad "tank" I've set up. The 1st was my 5g cube. Both resulted in a TON of floating debris, as the end pictures will show. I really wish I'd used sand, but was worried about making too tight of a layer (I haven't been able to find pool filter sand, yet). I don't think I'll be converting any of my larger tanks to this method, simply because of the mess. Even this 2nd time around, when I carefully wiped the glass clean prior to adding gravel & water, there was a lot of stuff free-floating. I'll try to get it cleaned up later... I've found that a finger swipe works better than paper towels.
Basically, moistened organic potting soil is layered on the bottom of your container along with any additional fertilizers you may wish to add (I used Osmocote - thanks Cobfreak for the tip), 1" thick. It's recommended to place a border of small-grained gravel or sand prior to planting. Set your plants into the soil and then cover all soil with up to 1" of your gravel/sand. Slowly (Did I mention, slowly?) fill with dechlorinated water.
Ms. Walstad uses lots of sunlight for her bowls, but I don't have that kind of placement available - so I'm using a 15w daylight bulb.
This is the 2nd Walstad "tank" I've set up. The 1st was my 5g cube. Both resulted in a TON of floating debris, as the end pictures will show. I really wish I'd used sand, but was worried about making too tight of a layer (I haven't been able to find pool filter sand, yet). I don't think I'll be converting any of my larger tanks to this method, simply because of the mess. Even this 2nd time around, when I carefully wiped the glass clean prior to adding gravel & water, there was a lot of stuff free-floating. I'll try to get it cleaned up later... I've found that a finger swipe works better than paper towels.
