Bio filter provides extra biological surface area for nitrifying bacteria to convert ammonia into nitrite and then nitrate. Trickle filter works by dropping water from fish tank through some kind of trickler (see A in diagram above) onto bio media (see B) and bacteria living on these bio media will help the nitrification process. Trickle filter also helps in degassing process, when the water trickle down, it contact with the air and some gas inside the water will be released to the air, such as carbon dioxide and excess nitrogen.
I use colander to create the trickle effect. This colander will be covered with some cloth, which function to filter out fine solid that escape the radial flow filter. Bio media that I use is K1 bio media, however I only have 1kg of them, which occupies about 6 liters of volume, so I added together some clay pebbles I have around to increase the bio media volume. Both media are wrapped inside a mesh cloth.
Radial flow filter is used to remove large solid waste from fish tank. The way it works is by directing the flow upward (see A in diagram above), and a standpipe to direct the flow downward, forcing the large solid to settle on the bottom of the tank. Outlet to the bio filter is positioned higher to avoid the solid to exit the filter.
One addition for this tank is I add an outlet (see B) with a ball valve to drain the tank including the waste out of the system. This drain pipe will connect to the sump tank to reuse the water, while I can use either mesh bag or cloth to collect the waste and put it into the mineralization tank
Using 50mm (2 inch) hole saw, I drilled two holes on the sides of a 12 gallon pail for the piping from fish tank and to the bio filter. While for the drain pipe, I used 22mm (½ inch) hole saw.
This is how I build the frame for the deep water culture (DWC) unit for my aquaponics system.
One thing I learned when working with varnish is I need a lot of thinner to dilute the varnish. The way I do it is by pouring some varnish into paint tray, mixed with some thinner, and paint a thin layer on the wood. However thinner evaporate quickly and the varnish eventually become thicker again, so I have to regularly add thinner to the varnish.
Not an easy task to do, some of the wood are bending so need to use more force to screw at the right place. Some are hard wood, so when I drilled it continuously, the drill bit become too hot and break eventually. If I use small drill bit size, it’s harder to screw, and some screws couldn’t go in, I had to cut them and replace with nails.
In the future, we plan to create a garden tunnel for the climbing and vining type of vegetables, such as bitter gourd, cucumber, passion fruits and others, which based on this structure layout, but using stronger materials.
Continuation from the previous materials list. These remaining materials were ordered online since I couldn’t find them sold here, and I simply don’t have time to go around the city to look for shop that sell them.
System cycle is a process to be performed on new system, to ensure nitrifying bacteria are colonizing the system. I plan to cycle the system using fish, by lowering stocking density and feed rate, then I need to monitor ammonia level daily to ensure it doesn’t exceed dangerous level. This is to ensure enough nitrifying bacteria to grow to convert those ammonia into nitrate, and this process will continue for about one to two months.
Water pH is one of the most important parameter to monitor. Initially, the system water pH will be a bit high (7 – 8 pH), and over time, the pH should fluctuate around 6 – 7 pH. For EC meter, it’s not so useful for aquaponics, but I think perhaps in future I’ll try hydroponics or fertigation, and EC meter is very useful to measure the fertilizer solution.
Other water test kits that will be beneficial to have are dissolved oxygen meter, various nutrient test meter (to test important nutrient such nitrogen, phosphorus, potassium, calcium, magnesium etc.) and thermometer. All these water parameter data will be useful later to analyze effectiveness of the system.
For this second batch of chilli planting, I sowed 3 types of chilli, which are cili besar (big type), cili geronong (type of habanero) and cili padi (bird eye chilli). Previous chilli trees which I brought together when we moved in last time were already dried up and dead. Also because I planted them along the gate wall, so its harder to clear up the weeds & bugs like to live there and damage the chilli fruit.
When the seedlings were 8 weeks old, I transplanted 9 cili besar, 9 bird eye chilli and 7 cili geronong to the soil at our house backyard. While the remaining I sent to village as requested by my mother in-law, to be planted around the house there.
This month the plants are 4 months old, and they started producing fruits.
I found that the soil quality affect the growth of the plant. Soil around the above chilli plant area is quite hard and don’t absorb water well (clay-like soil). The root can’t penetrate deeper into the soil & can’t get enough aeration to assist nutrient absorption. Chilli needs well-drained media such as coco peat or top soil mixed with compost, so that the root can uptake the nutrient while the media is draining or drying up. If it’s wet constantly, then the root might become rotted.
Here also I found that chilli plant that exposed to maximum sunlight will produce hotter & spicier fruit. We always used about a quarter of the cili geronong in our cooking, since the spicy fragrant & taste is very strong.