Murray
23rd January 2010, 08:29
I thought it might be useful to start a discussion re Grow Bed Media....Which is best? .....Is there a best?.....What types can be used.
Here is an old post of mine (in part) that serves as a starter.
Re: What is the best grow-bed media?
These questions resulted in some interesting and diverse responses. What I got from those responses was that the most important issue in grow beds is stability, both in temperature and biology. .......
I believe that to be true no matter what media is used or what depth of grow bed is used. Stability for the system as a whole is very important and is a factor in long term success and ease of operation.
That was the general position of those who favoured 300mm (or deeper beds).....and it was limited to gravel or clay pebble media.
Gravel and/or clay pebbles are the most commonly used grow bed media, but there are many more types of media that's for sure.
Gravel because it is low cost, readily available and it works. Clay pebbles, mainly because they look nice and are easy to work with. Some folk who live in apartments for example, just have no way of getting ordinary gravel.
I was the first (in this group anyway) to attempt to grow plants aquaponically in Coco peat. I was told it would not work.
It did, and very well, except for the fact that it discoloured the water returning to the fish tank. In fact after a few weeks the water took on the colour of very strong coffee.
I experimented with several different flood and drain methods.
The one that worked the best was a one way system where just enough fish tank water was added to wet the bed with no water draining out the bottom. This overcame the discolouration problem, as I was not returning the water to the fish tank.
It was a bit too labour intensive because I did not have a good timing device at that time that would have enabled me to automate the process.
I have not bothered with it since.
I grew carrots and potatoes and a variety of salad plants. They all grew very well. I have photos of that particular bed. I will dig them up later and post them up here.
It is far more risk averse than a gravel/clay pebble grow bed - it can last for several days without additional water.
In a conventional flood and drain aquaponics system there would be serious problems with the rest of the system if no water movement had happened for several days. The plants would be fine, but the fish would most likely be dead.
I imagine the above statement pre supposes that the grow bed's in question would be satellite grow beds that are watered by the use of a timer or by hand and not part of the regular cycle of the aquaponics system. If that is the case then coco peat or similar media would be an excellent choice for the grow bed in question.
In fact any concoction for a grow media is possible because the water is not being recirculated in the aquaponics system. Some members on this forum use water from the fish tank to water their regular dirt garden, with good results.
Auto pots come to mind as another alternate to the standard aquaponics model.
The standard aquaponics model pre supposes recirculating, as aquaponics in modern times has come out of recirculating aquaculture and recirculating hydroponics. Obviously there are variations to that model.
The best media is the one you can most easily get and afford, and the particular aquaponics model you wish to follow.
Here is an old post of mine (in part) that serves as a starter.
Re: What is the best grow-bed media?
These questions resulted in some interesting and diverse responses. What I got from those responses was that the most important issue in grow beds is stability, both in temperature and biology. .......
I believe that to be true no matter what media is used or what depth of grow bed is used. Stability for the system as a whole is very important and is a factor in long term success and ease of operation.
That was the general position of those who favoured 300mm (or deeper beds).....and it was limited to gravel or clay pebble media.
Gravel and/or clay pebbles are the most commonly used grow bed media, but there are many more types of media that's for sure.
Gravel because it is low cost, readily available and it works. Clay pebbles, mainly because they look nice and are easy to work with. Some folk who live in apartments for example, just have no way of getting ordinary gravel.
I was the first (in this group anyway) to attempt to grow plants aquaponically in Coco peat. I was told it would not work.
It did, and very well, except for the fact that it discoloured the water returning to the fish tank. In fact after a few weeks the water took on the colour of very strong coffee.
I experimented with several different flood and drain methods.
The one that worked the best was a one way system where just enough fish tank water was added to wet the bed with no water draining out the bottom. This overcame the discolouration problem, as I was not returning the water to the fish tank.
It was a bit too labour intensive because I did not have a good timing device at that time that would have enabled me to automate the process.
I have not bothered with it since.
I grew carrots and potatoes and a variety of salad plants. They all grew very well. I have photos of that particular bed. I will dig them up later and post them up here.
It is far more risk averse than a gravel/clay pebble grow bed - it can last for several days without additional water.
In a conventional flood and drain aquaponics system there would be serious problems with the rest of the system if no water movement had happened for several days. The plants would be fine, but the fish would most likely be dead.
I imagine the above statement pre supposes that the grow bed's in question would be satellite grow beds that are watered by the use of a timer or by hand and not part of the regular cycle of the aquaponics system. If that is the case then coco peat or similar media would be an excellent choice for the grow bed in question.
In fact any concoction for a grow media is possible because the water is not being recirculated in the aquaponics system. Some members on this forum use water from the fish tank to water their regular dirt garden, with good results.
Auto pots come to mind as another alternate to the standard aquaponics model.
The standard aquaponics model pre supposes recirculating, as aquaponics in modern times has come out of recirculating aquaculture and recirculating hydroponics. Obviously there are variations to that model.
The best media is the one you can most easily get and afford, and the particular aquaponics model you wish to follow.