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PostPosted: Mar 15th, '20, 00:04 

Joined: Mar 12th, '20, 20:55
Posts: 2
Gender: Male
Are you human?: yes
Location: Hangzhou
I'm British, but living and teaching at an IB kindergarten in China. I was considering creating a small scale aquaponics system for fun and to prepare for creating a bigger one in the future, and have now been told that the next inquiry unit I will need to teach my class will be about water. We'll need to cover water conservation, pollution, uses of water, and other things as practically as possible. I've asked my boss to find space to create an aquaponics system at the school and am hoping to run some ideas by you guys.

My background:
Experience of keeping freshwater tropical fish. Basic knowledge of things like hardness, PH, the nitrogen cycle, and consumer water tests.
Some online research about Aquaponics, including some of this forum.
A bit of experience growing herbs, potted plants, bonsai trees, etc. One time successfully growing corn to harvest outdoors at a previous school in Guangzhou.
Presently my class are trying to regrow vegetables from their kitchens!

Outline of the intended system:
The school is in an urban part of the city of Hangzhou, China, and has a (very) small outdoor space. There may also be space available on the flat roof.
I want it to be big enough that the water chemistry is stable and it can comfortably house a couple of small examples of edible fish without overpopulating it.
I would like to be able to grow enough vegetables that twenty children and a couple of teachers could at least try what we grow.
My inclination is to grow non-fruiting local leafy stuff like spinach, pakchoi, and lettuce so that success means success, and failure means small plants that still give us a little nibble.
My preference is to pair up a system like the one below that looks user-friendly...
The attachment 2.jpg is no longer available

...with a fairly substantial plastic container like the one below in the region of 120-150L. It seems like it might hold up to approx five tilapia-sized fish. My intention would be to get fingerlings for a local edible variety of farmed fish so that they can handle the climate and add them as the plants start to grow.
The attachment 1.jpg is no longer available

My biggest uncertainties are:
1) If/how to cycle the system and get things going. Rapidly growing plants will keep the water clean enough for the fish, but may not get that far without fish present in the first place.
2)Whether additional biological filtration media is necessary, or if that is provided by the sponge plant inserts.
3) Do I need to worry about chemicals in the tap water and what should I test for? People here mostly drink RO filtered tap water, me included.
4) How dechlorinating is done when you intend to eat what you grow. How sure can we be that dechlorinator is safe? Or do we evaporate chlorine? I guess I need to look into the composition of local tap water and possible chloramines.

I'll keep thinking it over, but all suggestions would be welcome, especially any considerations that I've missed.


Phil Wareham

These original Taobao links for the items may or may not work where you are. They're the same as the photos above. ... 0774913083 ... 9049655431

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PostPosted: Mar 25th, '20, 10:55 
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Joined: Mar 13th, '20, 12:07
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Location: Jacksonville, FL USA
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Location: Jacksonville, FL
<---- American.

If i did the conversion right then that is a roughly 35 gallon tank. I would try for bigger. If you can find 50 gallon blue plastic drums, those make excellent small scale and starter systems. Do a search for barrel ponics or PVC aquaponics. When it comes to making a system you imagination is your limit. I find buying pre-made things expensive. There has a been a couple of times i saw something pre-made and cool looking, but it cost me a fraction of the price to build it myself that includes purchasing new tools. Like the grow towers i made.

Personally, i would go with that white tank as a sump, get a large main fish tank. Something 40 gallons or more. For piping, Use 4 inch sewer pipin zig zaging down 4 by 4 post. Since its for school and you probably need to save money, you can use plastic cups and put holes in them. Sump tanks are great because your fish tank water level wont fluctuate and using a Solids lift drain all the wast will accumulate in there for easy clean out. ... vc-garden/ ( By zig zagging the pipes, you can go as high as you want with 4X4 fence posts as suports)


https://project.theownerbuildernetwork. ... ic-system/ (i would not drill holes in the vertical pipes, i would cut a slit length wise, then hot dog fold some plain trim to fit air filter (basicly make a zip grow tower).

You can also turn old fish tanks into DWC. Just float some herbs in there. I do that with 40G aquariums.

1) You do not need to wait for the tank to Cycke to add plants. Go ahead and add them. I have excellent plant growth during the fishless cycling. Do a fishless cycle. Get your hands on some plain janitorial ammonium or ammonia. Make sure its unscented. Shake the battle and make sure it does not foam. To start raise the ammonia level to 2 PPM. Let it sit until Have nitrites. Do not add any more ammonia till it reads zero. Then add enough to bring the amonia to 1ppm. Becarefull with ammonia and dont be afraid to let it sit. The Nitrobacter wont grow well when there is ammonia pressent. So i typical try to keep my ammonia levels and nitrites. There are a few artcles on here and on google about fishless cycling, one thing they dont mention is the presence of ammonia retards the Nitrobactor growth. So keep it light and low. You are cycled and have a strong biofilter when you can dose 1ppm of ammonia and 24 hours later you have 0 Amonia, 0 nitrites. Normally tanks my tanks 1 to 2 months to cycle. When you add fish, slowly increase their feed so your bacteria have time to grow. You dont want to cause a mini cycle.

2) Depending on stocking levels, you shouldnt need filtration. Between the roots and walls of the containers you should have ample surface area to colonize. If its a concern for you then get a cheap air operated sponge filter. It adds extra airation and biobiltering. I have them as backups for incase i loose power. You can never over filter. Most times when we add filters its more to remove solid waste. Not a big deal for small scale and removing excessive solid waste will be a part of the routine maintenance.

3) Yes. Just Chlorine or Chlormine and knowing would make a huge difference. Chlorine can just be off gassed in 24 hours with sunlight and air stone. Chlormine is a lot more stubborn. You can also dechlorinate with vitamin C. One vitamin C tablet will dechlorinate a standard bath tub. The problem with RO water is you just took out all of the minerals out. The PH will be unstable aswell. If its just chlorinated tap, water, i would fill the system and start it up. Toss in 1 crushed vitamin C tablet per 50 gallons. Chlormine will take some research to get rid of. I wont lie, if i am having an emergecy and need to do water changes or top ups ASAP, i will just use the standard water conditioner. I try to be ready and prepared at all times though with dechlorinated water that has been off gassed. I would top up with dechlorinated tap water. You will have High PH in the begining, but after a while, you will need to control PH up and toping up with stable tap water will help.

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