How and why will it sustain ITSELF?

We have tried to create a food chain of three trophic levels. With the research I have done I know that the spider does consume ant in the wild so I believe it will happen in the eco-Colum. Through observation I found out that the ant consumes grass and other plant materials that we have planted in the terra zone. It will also be kept going by the sun which will provide sunlight for photosynthesis

Our terra zone

Will be self sustaining because our the plants are releasing oxygen through photosynthesis. Our back up for if plants die is that we have planted grass seeds in the potting soil mixed with some sandy soil as we never had any loamy soil in the garden. We have a small aqua zone above for administering small amounts of water over a long time, this should all be enough to keep the ant and spiders going for 8 weeks.

Decomposition zone

is self sustaining even though it has no trophic levels the fruit will decompose and the fungi growing and dying will keep the decomposing going for 8 weeks. it is all decomposing in and on top of the potting soil. This has pieces of small plant material that will decompose over a longer period of time

The aqua zone

will stay self sustaining because of the water plants we put in so that it has a ready supply of oxygen so that it does not stagnate. We will find out any trophic level later under the microscope.