Coastview Aquaponics seeding technique

[Chris Smith]

Until recently all the work at Coastview Aquaponics has done by our family. Our farm has grown in size and has evolved over the last year. We have improved on the efficiency of our day to day work to save us labor/time. During the evolution of our farm we have constantly been improving on techniques that we have learned. One of our improved techniques is our new seeding process. We have been using this new seeding technique since October 2010 and it has proven itself well over multiple harvests. Now that this technique has proven its self we think it is time to share.

 We used to use a coconut & vermiculite mix in 2" net pots that were placed into 32 cell starter trays. This worked OK for us but we had a poor overall sprouting rate. Sometimes the seeds would sprout then die once touching the coir.  Sometimes we would have a bad block that would not sprout anything at all. We later learned the coconut was imported from overseas.

 

Here is an example of poor germination with coir mix. Every cell was planted at the same time and only some of them came up.

 

 

 

 

 

 

 

 

 

 

We began experimenting with alternative medium for seed sprouting. We tried many different mediums and had the best success with black volcanic cinder. This medium is local produced and readily available when living on an active volcano.

Black volcanic cinder is as light as hydroton if not lighter. Lots of it will float if filly flooded. Cinder is very porous and has more surface area than standard gravel. It has excellent wicking capacity in 2" net pots. The cinder is very easy to recycle and use again.

The cinder from the quarry is very dirty with lots of fine material mixed in with it. We screen and wash it to size grade and to remove the sand and silt. The larger cinder is used for gravel beds and the small cinder is used for seeding. The sand/silt is used in our wicking bed medium.

We now use our newly developed technique of seeding net pots directly into our sprouting rafts(2'x2'w/ 61 holes) using cinder as the sprouting medium. We line up 4 rafts at a time, insert net pots, then pour the cinder over tho top of the rafts. Using a small hand broom we broom the cinder into all the net pots and then broom off the excess.We are able to fill 4 rafts(244 net pots) with media in less than 10 minutes.

 Previously we seeded net pots in sprouting trays that would be later transferred into the same rafts after 7-10 days. We now eliminate the labor of transferring from sprouting tray to raft which saves us hours a week. We have shifted away from pelleted seed to using conventional seed(mostly grown by us). Raw seed tends to fall into the voids in the cinder to a perfect depth. The cinder has a wicking capability and if the bottom of the net pot is sitting in water then the seed on top will have adequate moisture for germination without rotting issues. The roots of the plants have all the oxygen they need in the voids of the cinder and grow very quickly.

 

Seeds germinating out of direct sunlight. I cover with plastic to keep them from drying out. After a 3 day germ I move them to one of the sprouting tables.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

We germinate the seeds our of direct sunlight for 3 days. By then the first seeds are looking for sun and I move them out to the seeding tables. We made custom seeding tables so that they would hold 8 sprouting rafts at 2'x2'. The tables have a constant 1" of water flowing through to provide fresh nutrients to the seedlings. These tables are like a thick NTF table. After two weeks the roots are long enough to need more water and we move the rafts to the nurcedry trough to make way for the next batch of seedlings.

 

These rafts are floating on 1" of water in custom sprouting tables. This table is a thick NTF table. The sprouts stay here for 2 weeks. We have 2 of these tables.

 

 

 

 

 

 

 

 

 

 

 

 

Here is out nursery trough. The plants grow in here for 2 additional weeks. They then move to the grow out troughs and get spread out to a grow out spacing.

[Harold Sukhbir]

Hi Jovan,

Jovan said: "abundance of knowledge flying around"

 

Harold says: Tell you what, run a personal trial of using the husk in at least three different ways. When you experience what's best for you, you'll know for yourself, and plus you can share with all of us here including people who may or may not know the pros and cons of your approach. Then we'll have a greater abundance flying around for sure!. Remember, what you learn by yourself no one can ever take it away!

[David Waite]

Has anybody used perlite in net pots. I am wondering if it will do what Chris is doing with black lava cinders. I am going to give it a test run. I to have given up on coco and switched to peatmoss and am having better success. It is a little wet though and am looking for something that wicks and breaths.

[Chris Smith]

Course perlite may work similar to cinder in wicking and breathing. I have not tried it though. For a time I used a mix of coir and perlite but did not like how the perlite floated when it got out of the net pot. Like Harold just recomended give it a try and report your findings. It would be great to find a seeding media that is more available to everybody at a cost effective price. I am lucky to live on a volcano that provides a great natural media.

[Michelle Silva]

Chris, not sure if you are referring to the large (1/4-1/2") size chunk perlite, but if so,..think I paid $25-30 a bag,.I had to buy quite a few bags as that is what I put in the larger bottom pots on my verticals (besides the expanded slate in some pots). I still have a little left,  but wouldn't buy more. The other perlite, that you may be talking about that I mix with coir was more than half that price (paid only $12-13 for a very large 18lb bag) but I think if I didn't mix it with the coir it may come out of the net pots. 

On a different note, think I might have posted before that I was planning on trying pine bark. I experimented with it on a very small scale and had a so so result. It was freshly cut mulch that I had an enormous amount of for free so would have been great if it worked. I had tested the ph and it seemed to be in an acceptable range, but there but there were many other variables at the time that could have been effecting growth/germination as well so may try it again.....good luck with your experimenting. I agree that sometimes it's the best way to learn..my whole system has been one huge experiment (a DIY hybrid system w/o any exact plans to follow) sometimes takes longer to learn that way and it got really frustrating at times, but also can be satisfying as well. I, like so many others here, strive for sustainability, efficiency and economy as well whenever possible. 

[David Waite]

Michele do you think the larger perlite would be better for net pots 2 inch size. I havent seent the larger size in my garden centers. where would be a good place to look. Thanks in Advance.

Michelle Silva said:

Chris, not sure if you are referring to the large (1/4-1/2") size chunk perlite, but if so,..think I paid $25-30 a bag,.I had to buy quite a few bags as that is what I put in the larger bottom pots on my verticals (besides the expanded slate in some pots). I still have a little left,  but wouldn't buy more. The other perlite, that you may be talking about that I mix with coir was more than half that price (paid only $12-13 for a very large 18lb bag) but I think if I didn't mix it with the coir it may come out of the net pots. 

On a different note, think I might have posted before that I was planning on trying pine bark. I experimented with it on a very small scale and had a so so result. It was freshly cut mulch that I had an enormous amount of for free so would have been great if it worked. I had tested the ph and it seemed to be in an acceptable range, but there but there were many other variables at the time that could have been effecting growth/germination as well so may try it again.....good luck with your experimenting. I agree that sometimes it's the best way to learn..my whole system has been one huge experiment (a DIY hybrid system w/o any exact plans to follow) sometimes takes longer to learn that way and it got really frustrating at times, but also can be satisfying as well. I, like so many others here, strive for sustainability, efficiency and economy as well whenever possible. 

[Michelle Silva]

RE: I'm not sure how it would work..could be OK, but it's not economical.if you're willing to pay that much then you may want to just buy hydroton..not sure if that's what Chris was referring to either..I've seen it called chunk.

It wasn't easily available in the local stores..eventually found a local orchid nursery that had switched to using something else and wanted to sell the last if what they had left..

[David Rairigh]

Oops.  Ignore this post.

[David Rairigh]

Sahib,

Have you found a supplier in central Florida?  I would be interested in trying out gravelite.  We're just getting a raft system setup where we're using two 4'x8x'12" media beds as fine filtration.  We were going to use a smooth river rock because hydroton is just so expensive but if gravelite is being sold as an aggregate for concrete then I don't imagine it would be too expensive.

Sahib Punjabi said:

Thank you Chris...very useful and informative :-)

 

I have had serious problems of seed germination using jiffy coir pellets and was considering moving back to Rockwool cubes (would love to try Black Volcanic Cinder but have not found it here in Central Florida). I have just come across "Gravelitet" which is an expanded clay lightweight aggregate (http://www.bigriverind.com/pages/products/TechSheets/GRAVELITETechI...). I am planning on trying to see how this work for seed germination. This is also what I am going to experiment with in my grow beds. I will share my results at a later date.

 

God bless,

[Sahib Punjabi]

Hello David,

 

Sorry for the late reply...just got a moment to check and reply. The local supplier for Gravelite is CEMEX and this is their local location :

 

Cemex

- Place page
www.cemexusa.com - 4010 Forsyth Road, Winter Park -

I believe that I paid $90 or so for 1/2 ton...this is roughly equal to 8 to 10 bags of Hydroton. Unfortunately it is more expensive than crushed concrete, but this is a totally different product and one that I have found to work. I am sure that you will be able to get a better price if you check further and call Big River direct to get their local distributors. I believe that the local distributor had mentioned that if I was near Boco I may be able to get a few 55 gal drums of this Gravelite far cheaper than what I paid. 

Good luck...let me know your results

God bless, 

David Rairigh said:

Sahib,

Have you found a supplier in central Florida?  I would be interested in trying out gravelite.  We're just getting a raft system setup where we're using two 4'x8x'12" media beds as fine filtration.  We were going to use a smooth river rock because hydroton is just so expensive but if gravelite is being sold as an aggregate for concrete then I don't imagine it would be too expensive.

Sahib Punjabi said:

Thank you Chris...very useful and informative :-)

 

I have had serious problems of seed germination using jiffy coir pellets and was considering moving back to Rockwool cubes (would love to try Black Volcanic Cinder but have not found it here in Central Florida). I have just come across "Gravelitet" which is an expanded clay lightweight aggregate (http://www.bigriverind.com/pages/products/TechSheets/GRAVELITETechI...). I am planning on trying to see how this work for seed germination. This is also what I am going to experiment with in my grow beds. I will share my results at a later date.

 

God bless,

[Michelle Silva]

 

The price sounds about the same price I paid for expanded slate..I was able to pick it up fairly locally. 

I looked at the specs on gravelite, wasn't sure of the size, is it 3/8"? 

I had used the expanded slate in some in the rafts but when harvesting it seemed a little easier to have something that I could just throw the whole root/medium on the compost pile, (coco coir/perlite) mix. On the flip side, it's not really that difficult to remove the roots from the slate and it can be reused.

[Chris Smith]

Gavelite looks like a good media. I now prefer to use a media that falls away from the roots after harvesting. I have been recycling the same seeding media now all year. I get most of it back and do not have to replace much due to loss. I never did like the floating perlite in my system.

[Christian James]

back to the use of Perlite - I've heard not to use it around fish - breaks down and the fish will eat it

 

Also, it adds a lot of work, but fluffing the Coco Coir helps after seeding it.  I've tried so many different ways w coir and up until last week was ready to give up on it, but I ordered some new seeds and switched to pelleted seeds, and OMG!  so much better germination rates.  3 of the 4 types I purchased had 100% within a couple of days, and hopefully the fourth variety will catch up.  I highly recommend buying from an online seed company like Johnny's Select Seeds rather than from Home Depot or the like!  you don't know what you're missing!