SMK Muhibbah Sandakan Sabah - Aquaponics Project.

What better place to do Aquaponics than in a school. This initiative is carried out by Teacher Mr. Fendi Hamid and pupils of SMK Muhibbah Sandakan Sabah. for Green School Award 2013 Project.
It's good for schools to get involved with Aquaponics, introducing alternative way of planting and fish keeping as in Aquaponics will make student aware of environment. It is also a way for them to learn a method that not traditionally practiced.

Follows are photos courtesy of Mr. Fendi Hamid on initial installation of their set up. I hope they will achieve what they are aiming for and gain useful knowledge in the process.

SMK Muhibbah is among the first school that take up Aquaponics for their school project. I wish them the best for this undertaking and hope other school will follow what this school is doing and I hope to hear more of their progress.

Growbed Layers

How deep is a growbed ?

This is a highly debated subject, to me the deeper the better. Not to say you cannot grow in shallow growbed, you can. I did use 6" deep growbed to save cost and weight of pebbles and I also use 12" growbed lately for hydroton and pebbles. If you have deep growbed, there will be more surface area for bacteria to interact and produce more nutrient and as the result will clean water better.

Plants benefit from this too since they will have deeper root zones and better support, deeper root zones will equal to more food for plants.

Aquaponics Growbed have 3 distinct layers.
1st layer, the top most is the dry or barrier layer that expose to sunlight. This Dry layer or zone is necessary to reduce evaporation and algae growth. This layer in a way provide a barrier from sunlight directly having contact to water, apart from already mentioned effect it also reduce direct heat which is important at sunny area.

2nd layer, the middle layer this is where in flood and drain system water constantly rise and fall, air and wetting the media for biofilter action converting amonia to nitrites and then nitrates for plant use. This also the Root Zone where most plant roots are found. The thicker this zones the better it is.

3rd and final layer is where water may not be able to drain, stays and where sludge accumulates, this zone are called by various names, I just call it Sludge Zones. At this zones breakdown of fish solids occur by bacteria and worm. It is crucial to have a good drainage in this final layer. Recommended to use larger pebbles to ensure it does not easily clog up.

The thicker the growbed means the thicker the 2nd layer where most plant roots are concentrated for nutrient, therefore shallow growbed although it work. It will be less root zones for plants.

Having said that, pebbles growbed can be shallow due to weight issue and also they are able to provide support to plants even at 6" of depth.

As long as you know what you are doing, its not much of an issue with regards to growbed depth. I recommend nothing less than 6".

Apart from above layers, growbed drainage is most important to ensure trouble free aquaponics set and good plant growth.
Putting larger pebbles or stones up to about 2 to 3 inches for the first few inches of growbed dependent on gb height is highly recommended. It is then follows by smaller pebbles or hydroton to top of growbed.
The larger pebbles is to ensure good drainage and the smaller for easy planting of seedlings and sufficient area for bacteria growth.

Update : 4th. August 2015

It is recommended to use pebbles or rock larger than above picture to ensure they are easily separated if the media need to be replace. With better designed siphon or SilosGrowbed method those pebbles at the sludge zone  are no longer necessary.

Hydroton Growbed Redo

One of the hydroton growbed giving me problem with its siphon. As I recall this particular growbed was the first that I tried with hydroton in my set.
Emptied the growbed and what needed to be done is to redo the siphon strainer. It was a quickie job few months back while I am trying out the hydroton. The strainer from start I know will eventually give problem.
During that time I was using 10 mm drill to make the strainer, but it was too big and letting hydroton through. As a temporary measure I glued plastic netting to make sure no hydroton  pass. Current design is 8 mm holes and no netting required.
Above the complete trouble siphon assembly, what needed to be done is to make 8 mm holes on the top and strainer holder as in current design.
Siphon removed from growbed to rework.
Smaller holes drilled and strainer holder is also drilled for water drainage. It was not done earlier, adding problem to the siphon operation.
Stand pipe and reworked strainer holder installed.
Completed siphon, bigger holes on top is not required. It is there because I reuse the same strainer to make smaller holes on the other side and just flip it over.
Old and new side by side for comparison, inner parts not change.
I decided to put first 2 ~ 3 inches with pebbles, they are better at drainage. Took me about 2 hours to redo and get it back operating. Hope it doesn't cause any problem to growbed nutrient level.

Kuchai Fruiting

Kuchai or that Chinese Chives flowering and now fruiting. I will try to collect those seeds and sow for seedling.
Sowing from "off the shelf" seeds was a failure, I need to try out from home grown batch. Maybe it will make a difference.
Will let those pods dry on stalk and collect it later.

Growbed Period and Tilapia Cycle.

I had been doing these for quite some times and decided to put it to paper, what I practiced in relation to Growbed Maturing Period and Tilapia Cycle.

This is for backyard and not intended as a guide for commercial venture where they will need faster Tilapia Harvesting and Growbed Maturity.
Above graphic representing the number of months in a year and at a location where sunshine is year round, no fertilizer or supplements except Iron in the form of few metal rods.

Growbed Maturing Period.

Stage 1 - Basic Maturity
Growbed bed maturity as most cases states at 6 to 8 weeks same as in normal aquarium, however in real situation this period can be longer depending on how well the water is controlled and other factor like aeration and sunlight exposure. At about 2 months there will be a sure sign of maturing.

During this period its best to try out simple plants to keep Nitrate in check.

Stage 2 - Intermediate (Medium) Maturity
Post Basic Maturity to roughly double the time needed as Stage 1. This is where bacteria and fish reaches an equilibrium and start to build up more and more nutrient toward sustaining full growth of plants and fish.

During this period, try various plants to ensure suitability in term of location, climatic conditions and whether suitable for Aquaponics planting.

Stage 3 - Full Maturity
This is at 6 months and onwards, this where system has reach its full potential and planting should be base on Stage 2 trial. Plants are grown to make it possible to harvest adequate quantity for household needs.

Tilapia Cycle

1 ~ 6 Months: Initial start of a system, fingerling are added and rear for 6 months with starter and grower feed.

7 ~ 8 Months : Fattening Period for Harvest, Normally Finisher are feed to these fishes.
Tilapia can be harvested after 8 months as in backyard setup, but I usually done it at end of the year after about 10 months due to slower growth that I wanted.

8 ~ 10.5 Months : Select few breeder like 2 males and about 5 females and keep them separate, watch closely, they could breed after 1 months. Separate those fry once detected and grow them in separate area and return breeder to stock for harvest.

10.5 ~ 12 Months : Once fry large enough at about 2 inches fingerling, you can start harvest those big tilapia for dinner.

Above are base on what I practice for household consumption and at a backyard environment.