Reader Jakub from Poland has been an aquarist for more than 20 years and has always loved to perform hydroponic and aquaponic experiments with his houseplants. In this neat little semi-aquatic composting system he has setup, he’s using a combination of aquaponics and worm composting (vermiculture) to provide all of the nutrients his plants need to thrive.
As Jakub describes it… My system may not look impressive, but it had to fit into my 5 sq. meter bedroom. It did. And it works! Here’s how…
This is my “pre-composting” tank. It’s an Atman CR-320 with a simple foam filter connected to the air-pump. Inside I keep few hundred Malaysian trumpet snails (Melanoides Tuberculata) and few dozen Red Sakura shrimp (Neocaridina heteropoda)…
I feed them mostly walnuts (the “empty” ones) from my allotment garden as well as some nut shells, dried walnut leaves and nettles. Their food source are also dead duckweed parts and bacteria living on the foam of the filter.
Composting in water goes VERY slowly, so the tank is not my basic composting unit. Instead, it’s a source of biologically active water and bacteria for the rest of the system…
Before I started my worm farm I used the aquarium water for watering my houseplants. It works – plants grow like crazy and I never had to buy any fertilizer. Walnut shells take few months to be slowly chewed up. I use them as a breeding ground for the shrimp which require some hiding place till they’re young and fragile. As for the leaves – it take my pets 2 days to eat through the soft tissue, and 1-2 weeks to chew up the rest…
Above the tank, on my tiny eastern windowsill I keep my aquaponic onions for onion greens (for the cottage cheese – yummy!). There’s hardly any light in that spot because of the balcony behind and our latitude (52 deg. N) which in winter makes days lasting for 5-8 hours of dim something-like-daylight…
The onions have enough sugar in their bulbs though to shoot even in such poor lighting conditions. They grow in expanded clay pebbles with aquarium water as a medium. Thanks to the air-stone I don’t have to change their water at all. I only add it as it evaporates.
The previous onion in the right pot was growing in pure vermicompost and was doing well. Now I switched back to clay pebbles as they’re more intuitive for me…
My worm farm is as classic as it could be: three buckets I recycled (upcycled?) after refitting the apartment. The bottom one is equipped with a faucet left from my rainbarrel. The middle one contains the first portion of worm castings from the previous year. In the top one there’s a layer of castings and mostly paper bedding. Occasionally there’s vegetable matter like those physalis leftovers from my garden and some old cotton bandages that I’ve found in the old locker…
I’m currently performing an experiment of feeding the worms mostly shredded paper and aquarium water as a source of moisture and bacteria for paper decomposition. It is said that worms eat bacteria. Nitrifying bacteria from the aquarium thrive on anything that is organic, wet and has large surface area – in my case it’s wet paper, so it should work. It is also said that paper decomposes in water in 3 weeks…
It took my aquatic folks some 2-3 times longer to eat a paper roll as a test. Without them I think it would just lie there for 3 years instead of weeks. So I put paper into the worm bin. So far so good – I add few handfuls of paper every week and it keeps disappearing. I only hope that it won’t lump into some chipboard brick in the bottom of the bin. Time will tell…
Yeah, I know there’s a power switch just next to the watering can – it had no other place to lie and I have to be careful with it…:) The can is being filled only when I’m watering my plants anyway. Every weekend I pour the aquarium water through 0.5 cm silicon tube down the worm farm and through the valve into the watering can. This way I flush the excess castings right into the compost tea and don’t have to rotate the buckets as they fill up…
I use only as much water from the aquarium as my plants require. When they’re all watered, I stop pouring water from the tank and turn off the valve. Excess water gathers in the bottom bucket as usual, being a source of moisture for fresh-added paper and the rest of the farm.
Compost tea is so rich that I not only don’t have to use any fertilizer – I also use the same potting soil over and over. When I need more of it than I have (when repotting), I use my secret box from underneath the worm farm…
This is the secret box (aka. “black box”;) It’s another experiment I perform. My first worm farm got cooked as I was adding foodscraps too fast, having only a handful of worms to process it. So I took the farm onto my balcony (it was spring with about 5-10 deg. C) to cool off, but the farm seemed dead anyway.
So I dumped it into 22-litre plastic IKEA Samla box with a lid, buried the farm contents under few centimeters of potting soil to suppress rot odors and closed it for a year in my wardrobe – as an experiment with anaerobic composting.
After a year the box was half-filled with… pure vermicompost as some of the worms survived even that (a YEAR in closed plastic box!). So I dug those worms out that I could find and used most of the contents of the box for repotting my houseplants. Worms that I’ve dug up went to a shiny new worm farm mentioned above and started their work in its first bucket.
At the same time I started collecting foodscraps into my IKEA box which took me 2 months of July and August. When the summer was over and the temperatures started to drop under 15 deg. C I filled it up with the rest of my “anaerobic” (vermi)compost, closed the lid and put it under worm farm till next summer. As you can see, there are traces of worms in the condensed moisture under the lid so some of them are still there…
I have a high hope for this box as a potting soil factory since I don’t use my worm farm for solid castings. Last year’s compost-from-the-box was loamy and required some mixing with the old, dried soil from my plant pots. So now I’m also collecting egg shells which I plan to mix with the contents of the box in the summer when the cycle is complete…
I predict that shells may loosen the soil structure, so it (hopefully) won’t require mixing with old potting soil. If I could just dump the scraps into that box, put some soil on top, then close for a year, using another box since – then 6-10 boxes would be enough for me to operate that way year-round. Hardly any maintenance – seems tempting, but I have to work out the loamy structure first, so I keep focused on one box at a time.
Last but not least – these are some of my plants. Forgive me the dusted leaves – we have terrible air during the heating season. The first one is my Daughter’s Dracaena. It’s about 3 years old and has grown 3-4 times since bought…
Next is my Wife’s Sansevieria Trifasciata Hahnii which have to be kept in a balcony box due to it’s growing rate. Every year we split it into 2-3 such boxes and it grows like a weed…
There’s also Bryophyllum pinnatum (aka. “Mother Of Plenty”) which I also keep in a balcony box within IKEA Socker greenhouse – from the same reason as it is with Sansevieria – to keep it in place and be able to lower the blinds on the window without harming its fragile leaves…
Last two photos are of my other Dracaena and Yucca plants that went too large to be kept indoors (32 sq. meters for a family of three – fourth on his way – and a dog). There’s also my neighbor’s Schlumbergera which has already doubled in size since I started to refill her watering can with my water. It’s supposed to bloom on Christmas but now it’s blooming year round…
On the last photo, the two yuccas in the front are two halves of a bigger one that I found on a street after someone left it broken apart. I never could stand throwing plants away, so I took it, put both halves in a pot with my older yucca plant and watered it with aquarium water. Both halves rooted quickly and started sending shoots around them (but it’s nothing special for yucca anyway)
There’s also (photo not available currently) Kalanchoe that someone has thrown out after it withered. People keep it as a seasonal plant – for a month or so – till it’s blooming.
Well, it doesn’t look pretty (I let my plants go wild) but it keeps blooming and it will be it’s 4’th year since I’ve started watering it my way… I keep it outside like yuccas mentioned above, because it became too big to be kept indoors. I also use my water for balcony plants, but currently there are only winter birds there crowding around my feeder;)
Hope you’ve found something useful (and convincing;) here. All the best for your plants and may your invertebrates live long and prosper! 😉 You can learn more about aquaponics here and setting up your own worm composting operation here.
If you like this idea, be sure to share it with your friends and inspire someone you know. Anything becomes possible with just a little inspiration…
