Magnesium Sulphate (MgSO4) or commonly known as Epsom Salt are use in agriculture to promote chlorophyll production. Certain plants like Tomatoes and Chili require magnesium for their better growth.
Epsom Salt is non organic, so if your aquaponics setup is on an organic track, you have to think twice before applying this to your set.
Looks like sugar and it is highly water soluble, application as a foliar spray is common. In aquaponics, adding to growbed near the water inlet is recommended.
You don't have to add much, one table spoon is enough for a medium size growbed. Monitor for changes in the vegetable or plants leaves and only add if you suspect that the plants "green" is not as green as you might expect. Epsom Salt is also good as a relaxant, where you can add it to warm water and soak your feed. This is what most people use it for. In a bath and foot soak, they are suppose to have a relaxing effect on the body. So if you use Epsom Salt as a foot soak, don't throw that water away. Put it it the aquaponics set, so nothing is wasted. Where to buy Food Grade (Recommended) Most Reputable Pharmacy, like Guardian, Boots and Watson Non Food Grade Agriculture Shop, they sell in bulk.
Slugs, millipede, centipede, ants and other crawlies can start to be comfortable in the growbed. How do we get rid of them ?
On flood and drain media base aquaponics, I recommend to flood the growbed. Most crawlies can't survive underwater for long period.
To flood the growbed first stop the siphon action by removing the enclosure bell as photo below.
or remove the siphon cap on the #strainerbell siphon as below,
Once the cap or bell has been remove, the siphon action will stop. This depends on the height of standpipe will cause the growbed to be flooded. If the standpipe is lower than the media height, it is advisable to remove some of the media or change the standpipe extender to a longer extender causing a flooding.
Downpipe photo of the siphon as below with replaced extender.
Once the growbed flooded, wait a while and you can now see many creepy crawlies start to make their way to the top of the growbed. This is a good time to get your slug picking chopstick ready and start picking.
Slugs
more slugs
and more slugs
Well have fun picking those slugs.. :) How to get rid of ants ?
For ants, I recommend that the high water extender are left there for a few days, and let the siphon operated as normal. Then replace it back to the ones that have water 1" below media height. I recommend doing this flooding monthly, to ensure slugs etc don't have time to multiply. It is such an easy thing to do anyway.
What will happen if you have too high water level in the growbed? Initially high water level will cause higher evaporation and water will be use more due to this. To ensure this don't happen it is recommended that the water level is at least 1 inch below the hydroton or media level.
Above photo the water level is about 1 inch below the hydroton and it is just nice for most setup. What else could happen? Algae and some time moss will grow, moss could turn into fern in some cases. Algae and mosses will compete with plants for nutrient and it also will make the growbed looks dirty as below.
As a general rule 1 inch water below the media is acceptable, this is the DryZone of an aquaponics growbed. This DryZone can be thicker depending on type of plants grown. A siphon with adjustable standpipe height is helpful in ensuring this water level is easily achieved.
Chelated Iron like Fe 13% EDTA are use in agriculture as a supplement to ensure yellowing leaves don't occur and enhance production of chlorophyll in leaves. They can be use as a foliar spray either on its own or mixed with common pesticide. It can also be administered through fertigation solution.
Fe EDTA in aquaponics we add to growbed either to the growbed or the fish tank. I would recommend the earlier since it will not be directly available to the fish in it undissolved form that those hungry fishes think it's fish food.
How much to add? As home setup I must say, I add only as much as it's required. They are extensive post in forums about how much to add with volume of water in your system etc but I don't bothered about it.
In aquaponics, water is constantly circulating so like ammonia in the fish tank iron will be continuously circulated in the system and the plants will uses as it needs. It is not like the foliar or fertigation method that may be excessive hence wastage upon application.
I have four growbeds in this CRAFTS setup, I put one tablespoon into each growbed at the water inlet. Usually it will be enough, nothing is wasted since it will be circulating in the system. This particular Fe EDTA works from ph range of 2 to 8. Most of my aquaponics set the ph is about 6.7 to 7.3, so it should work. Ok.. that the small tips. Where to buy; Nine Top Trading Drive there using Waze: http://waze.to/lr/hw284z42xf
Insect and caterpillar are a common threat in aquaponics setup just as in any garden. When you do aquaponics, most of the time people automatically thought it is organic. To be honest Aquaponics and Organic are two different things. A setup can be aquaponics and organic at the same time if its follow the strict organic farming or gardening guidelines. However it will be difficult if you are just starting out on aquaponics and at the same time trying to follow the organic requirements due to too steep a learning curve. Those that has practice either aquaponics or organics for a long period of time then it will be an easier process, especially if they are already practising Organic gardening. I had tried various organic spray to control bugs, caterpillars etc, none seems to work therefore I use non-organic insecticide to get those under control. Some aquaponics purist may not agree with this, but it's okay. Everyone are entitle to their own way of doing things. I had use non-organic insecticide as a direct spray onto the plants in my growbed, and so far I do not have any fish killed. I follow strictly to the instruction on the label, observe all precaution and most of the time I will use a more diluted mix.
A safe way to apply non-organic insecticide is to apply them away from the growbed, this is easy if you have plants grown in pots where they are easily move to a safer environment for spraying.
Even through I practice direct spraying onto growbed plants, those plants that in pots I'll spray them away from growbed and the fish tank.
Disclaimer This is how I practice using non organic insecticide, I'm not in any way recommending or endorsing any particular chemical, poison or manufactured product for use in the Aquaponics practice. Any usage of any poison or chemical is solely at your own risk.
Many people has been asking me how do I sow seeds for Aquaponics, whether I sow them in soil or directly to growbed. Well it all depends on type of seeds, if it extremely small like Lettuce seeds I'll probably sow them in soil first. If Cili, Tomatoes, Kailan, Okra etc I'll sow directly to the growbed. Those cheap seeds I'll sow direct regardless of size, because sometimes it just not worth the extra trouble of preparing a seed tray. It is your choice whichever is convenient to you. Now it's time for me to sow few seeds, since I have one vacant growbed to use. These seeds has been kept for quite a while, so I had to use most of it rather quickly before it expires.
All the seeds I sprinkle directly to growbed for these sowing, I have too many to use so, just sow more than I need. Cili, Kailan, Okra and few other vegetable seeds directly to growbed.
Few will grow, that's all that I wanted.
After all seeds has been sprinkle onto the hydroton I'll use my fingers to "rake" them over to get them down to water level. It is also best to stop siphon action by maintaining water level at top of standpipe.
If your growbed water level is low, meaning your growbed dry zone is deep, it is important that you water the seeds daily until they germinate. If this dry zone is shallow the seeds can reach water then it's not required to water. Sometimes when I sow in potted hydroton, I'll remove a layer of hydroton until I can see water reaching surface then I will sow the seeds at that level after which I'll cover the seeds with the earlier removed hydroton. So that's how I do it, will update this post once seeds germinate and at transplanting.
This tool I made during the days that I uses pebbles instead of hydroton in my growbed. Pebbles are very hard and heavy, they will damage seedling if we are not careful during planting.
(Photo to be added here)
The tool are made from PVC pipe and uses to force the pebbles from the seedling during planting. With hydroton this may not be needed, but for the sake of those that uses pebbles as growbed media, this tool can be helpful. A repost video below.
Seedling are fragile and they break easily. To reduce chances of damage while planting seedling, growbed should be flooded to make the hydroton more movable.
For flood and drain growbed using siphon, the siphon need to be stop from operation either by stopping water inflow or by removing the siphon enclosure bell (cover).
With growbed flooded it is easier to arrange the seedling and get its roots deep down.
Once the planting is completed, reinitiate flush by restoring the siphon to its operational state.
This is a simple way to temporarily protect a new seedling or cutting from the elements. Use another pot to cover them, this way strong sunlight or heavy rain will not damage the plants. Slot in the pots gives some sunlight to get the seedling or cutting going while maintaining air circulation.
Pots are secured by using clips to ensure they are not blown away or toppled by heavy rain.
It is best to use hanging pots since they already has holes for wire attachment. Otherwise you will need to secure it either by making holes or different type of clips.
All done, good for a few week depending on type of plants that you grow in the pots.
With much of the experimenting over on the Ornamental set, it time for reducing its outlet sound. At times the siphon outlet can be loud and it's no different on this smaller set. The easiest way to reduce the sound is to put a muffler end on the outlet.
Muffler end is made by drilling few holes on the outlet final downward tube , this works as to let air water mix and thus reducing the sound.
This muffler also act as an aerator giving much needed oxygen to the water. If needed to reduce noise and giving oxygen to water, this is the simplest way to do it.
Water loss is a big issue over here in hot equatorial weather especially during dry spell. It will affect more on smaller system, and to be away for a week or so then it could be a disaster waiting to happen.
To compensate during this period of hot spell or unattended system running I decided to make a trickle water compensation into my fish tank. I saw it was done by Zulhairi in his blog site and it's a good idea.
I use a small tap and hose that commonly use for water filter and just metered the flow rate by adjusting tap position. I need about 5 ~ 6 liter per hour flow rate. The measuring container above was use to check how much water flow after about 15 minutes. The rest is just adjusting tap to get the approximate correct flow. Update 22/7/2013 : After 2 days of operation, I readjust water to 4 Liter/hour flow rate. Will be monitoring these next two weeks.
Once I had obtain the correct flow, the small tap handle is removed and safe-keep, this to ensure no accidental closing or opening of this tap that could cause major problem to my set. Basically to keep off "small fingers" from messing with it. Full water shut off is by closing that water cock on the wall below the tap if trickle flow is not needed.
Water trickling into fish tank. Chlorine is not a major concern since the flow is too small. Update : 11 August 2013 I left my Aquaponics set unattended for 5 days during a festive holiday, no problem at all with water level. It maintain just nice throughout the period running by itself. Water level sufficient and no sign of over spilling or too much water. Adjusted rate is 4 liter per hour drip. Total water volume in system is about 1200 liter and at 4 liter its will be about 96 Liter daily @ 8% compensation.
Nutrient supplied to plants in Aquaponics are from the fishes and the fish food dissolved. These sources of nutrient lack Iron, in Aquaponics Iron deficiencies result in yellowing of leaves.
There are commercial products that address this and there also some methods that are practice of old.
Chelated Iron is one common commercial product use, it is added to water via grow beds every about 2 ~ 3 weeks or so, this will cure plants of the Yellowing Leaves symptoms.
Blood meal also a source of Iron can be added to provide Iron to plants.
Old Farmers practice rusty nails and scrap metals in a bucket of water, and pouring it near tree trunk that have yellowing leaves interest me.
Does it work, those old timer may not heard of Chelated Iron, but they sure do have a lot of nails and scraps.
To practice what those farmers did, I collected scrap iron from around my back yard and put it in the tank.
At first I put it in the filter, but recently I found some long iron rod, those that for construction work they are too long for the filter so I use PVC water pipe to hold them.
What’s needed is a PVC pipes big and long enough for the job and 2 end caps. Drill holes along the pipe and place iron rod inside, capped the pipe and throw it in.
You can attach a string to it for easy retrieval or just without.
Photo shows the PVC pipe and Iron inside and this one with it in the water.
