Aquaponic Gardening

Here are my notes from book "Aquaponic Gardening - a step-by-step guide to raising vegetables and fish together" by Sylvia Bernstein.


Nice book about how plants and fish can coexist together promissing "fresh fish and vegetables, grown hassle-free at home". To me it doesn't seems so hassle-free, there are many details to catch and a big home with land is needed, in some not too cold climate, for aquaponics to be some real source of food, still it can because a worth it and noble hobby I'm sure. One new thing I've learned is that plants don't really need soil to grow. Of course under special circumstances and that is that the nutrition comes from fish, not from soil with microorganisms. Another interesting fact is, how important oxygen in water is for both fish and plants. You can drown you plants roots with oxygen deficient water. In other words, the water has to flow and exchange to be of good quality. Just out of curiosity I've asked my friend Hamish Graham, an expert on oxygen for people, it oxygen in water makes any difference for people too and he told me that not really. But for plants and water life it's essential.

  • p5 see www.aquaponics.org.uk
  • p12 Becaue it was unrealistic to think that I could live off blogging and running a niche community, that winter my husband and I also started a company called The Aquaponic Source
  • p21 Aquaponics is the cultivation of fish and plants together in a constructed, recirculating ecosystem utilizing natural bacterial cycles to convert fish waste to plant nutrients. This is an environmentally friendly, natural food-growing method that harnesses the best attributes of aquaculture and hydroponics without the need to discard any water or filtrate or add chemical fertilizers. --Aquaponic Gardening Community, November 2010
  • p22
  • p61 So let's say you start your system in early May and it takes six weeks to "cycle" (start the biofilter), and you are using the fishless cycling technique we discuss in a later chapter. You can now introduce your fish, which you have hopefully selected to match the temperatures you will be expecting over the summer, A common choice is tilapia. The most readily available tilapia will be fingerling size (about two inches long). Those will take nine to twelve months to grow out to harvestable, plate-size fish, depending on their original size, how ideal their conditions are and their feeding regime. This takes you into something between March and June of the following year! Your plants will have long since died, and the power bill for heating your fish tank over the winter will be extreme!
  • p65 Ask anyone who has an active greenhouse, especially an aquaponics greenhouse, and they will tell you what a special place or renewal it is for them.
  • p67 You may want to look for back-up aerators used for keeping minnows alive; you might find some at a sport fishing store.
  • p86 Become friends with rubber gaskets and marine grade silicone.
  • p88 Finally, these recommendations assume a fish stocking ratio of 1kg mature fish per 40-80 litres.
  • p95 The best way to paint your IBCs is with an automotive plastic primer, then use an industrial grade spray enamel as a top coat.
  • p104 Steps for planning your system: 1) Determine the total grow bed area in square meters - 500g of fish for every 0.1m² of grow bed surface area at least 30cm deep, 1kg of mature fish per 40-80 litres 2) Grow bed and fish tank - start with 1:1 of grow bed volume to fish tank volume. You can increase that up to 2:1 once system starts to mature, both bad and tank will be heavy and must be food-safe 3) Grow bed - at least 30cm deep, use media guard 4) Fish tank - 1000+ litre create most stable aquaponics system
  • p106 Magnetic drive pumps are best because the motor is in its own sealed compartment and should never leak any oil into the fish tank water.
  • p113 The overflow is as tall as you want the water level in your grow bed to be. Around 25cm is optimal in a 30cm-deep bed because it gives an inch or two of dry media at the top of the bed, plus it allows for a little extra height for the water to flow over the top of the overflow pipe.
  • p126 Aquaponic media rules of thumb: must be inert - i.e., won't alter the pH of the system; must not decompose; must be the proper size (12-18mm aggregate is optional); the most widely used media types are LECA (lightweight expanded clay aggregate), lava rock, expanded shale and gravel; if you choose gravel, understand its source and avoid limestone and marble as they could affect your pH
  • p138 Aquaponic water rules of the thumb: purity, temperature, oxygen, pH
  • p150
  • p155 I've used largemouth bass, hybrid striped bass, crappie, yellow perch, catfish, oscars and Jack Dempseys... with varying results.
  • p156 Commercial aquaculture operations feed their fish as often as once an hour so as to feed their adult fish as much as 1 percent of their body weight in feed per day, and closer to 7 per cent for juvenile fish.
  • p158 Homegrown feed: duckweed - this fast growing aquatic plant doubles in mass every day when in its ideal environment; worms - earthworms, sludge worms, bloodworms and composting red worms, black soldier fly larvae
  • p159 First, I recommend that you "purge" your fish by putting them in a tank of clean water and not feeding them for a few days before harvesting. While not absolutely necessary, this process gives the flesh a better, cleaner flavour.
  • p168 If you grow a cold-water fish such as trout, however, you will be limited to only growing cool season plants. Warm season plants can't survive root zone temperatures below 13°C, and won't begin to thrive until the temperature is above 18°C. Tomato plants, for example, prefer a root zone temperature of 24°C, which is happily the same temperature that tilapia thrive in.
  • p184 Finally, bacteria require a pH between 6.0 and 8.5 in order to metabolize and reproduce. The optimum pH range for Nitrosomonas bacteria is between 7.3-7.5.
  • p185 Then a few years ago someone got the brilliant idea to add composting worms to their aquaponic media bed. Worms are one of nature's great garbage disposals. As Murray Hallam is fond of saying, they are aquaponics "secret ingredient". Not only do they break down and digest the solid waste and dead root matter that plants slough off, but in return they give us another one of nature's perfect fertilizers. The waste from worms is called worm castings or vermicompost, and when it is steeped in water it becomes an incredibly potent fertilizer called "vermicompost tea" or "worm tea".
  • p190 To do their testing, most aquaponic gardeners use a product by Aquariom Pharmaceuticals Inc. called the API Freshwater Master Kit.