Aquaponics Digest - Mon 04/09/01
Message 1: Small Hatchery
from dreadlox 'at' cwjamaica.com
Message 2: Electricity and plant growth
from "Adriana Gutierrez"
Message 3: Re: Grow Bed Media
from Mark_Brotman 'at' kinetico.com
Message 4: Re: Electricity and plant growth
from "Elisheva Ruth"
Message 5: Re: Small Hatchery
from RalphMcl 'at' aol.com
Message 6: Some tinkerer Sites (Not Weird)
from marc 'at' aculink.net
Message 7: Polytanks leaching?
from spettels 'at' newnorth.net
Message 8: Used equipment?
from spettels 'at' newnorth.net
Message 9: Re: New Guy with problem
from S & S Aqua Farm
Message 10: Re: Grow Bed Media
from Ronald Polka
Message 11: RE: Grow Bed Media
from "Hurst, Steve ( China)"
Message 12: RE: Grow Bed Media
from "Hurst, Steve ( China)"
Message 13: Cleaning Grow Beds in S&S system was: Steve, change your underwear!!
from Bill Patrick
Message 14: Re: Cleaning Grow Beds in S&S system was: Steve, change your underwear!!
from "TGTX"
Message 15: Re: Polytanks leaching?
from S & S Aqua Farm
Message 16: Re: Cleaning Grow Beds in S&S system was: Steve, change your
underwear!!
from S & S Aqua Farm
| Message 1
Subject: Small Hatchery
From: dreadlox 'at' cwjamaica.com
Date: Mon, 09 Apr 2001 02:19:05 -0700
I met with Charlie Schultz today here, also a list member, it was a
great time. We visited 4 tilapia farms and one shrimp farm, Im tanned a
shade darker, being on the back of the van!!
Im really thinking along the lines of the tank system of producing fry,
using hybrids, and also other peoples experiences with growing their own
fry, in a similar manner.
Im aiming for a system where I wouldnt have to do a lot of sex reversal.
Im willing to take the plunge but just need a few other opinions.Id love
to hear especially about people having results of 100% or near 100%
males.
Thanks,
Mike.
| Message 2
Subject: Electricity and plant growth
From: "Adriana Gutierrez"
Date: Mon, 9 Apr 2001 04:48:03 -0500
I came across an interesting summary of research into the effects of
electricity on plant growth. This is meat for some of you tinkerers
out there. Just be careful or you will wind up with a "fish fry" or
worse, on your hands.
Adriana
http://www.rexresearch.com/elcultur.htm
| Message 3
Subject: Re: Grow Bed Media
From: Mark_Brotman 'at' kinetico.com
Date: Mon, 9 Apr 2001 08:13:29 -0400
Steve,
A good way to sterilize soil in the tropics is to put it into a (clean)
black plastic drum, cover and put it on it's side. Leave it a sunny spot
for about a week, depending on the clouds and rain. Roll once a day to
mix. I bet this would work for your lava-type rocks well, as long as we're
not into your rainy season.
Mark
| Message 4
Subject: Re: Electricity and plant growth
From: "Elisheva Ruth"
Date: Mon, 09 Apr 2001 08:47:58 -0400
Can you send the summaries and sources?
Thanks.
Eli
----------
>From: "Adriana Gutierrez"
>To:
>Subject: Electricity and plant growth
>Date: Mon, Apr 9, 2001, 5:48 AM
>
> I came across an interesting summary of research into the effects of
> electricity on plant growth. This is meat for some of you tinkerers
> out there. Just be careful or you will wind up with a "fish fry" or
> worse, on your hands.
>
> Adriana
>
> http://www.rexresearch.com/elcultur.htm
>
>
| Message 5
Subject: Re: Small Hatchery
From: RalphMcl 'at' aol.com
Date: Mon, 9 Apr 2001 09:18:39 EDT
MIKE
CHECK OUT WWW.TILAPIA AQUACULTURE INTERNATIONAL
JUST A SUGGESTION
RALPH
| Message 6
Subject: Some tinkerer Sites (Not Weird)
From: marc 'at' aculink.net
Date: Mon, 09 Apr 2001 11:43:10 -0600
http://www.engr.uconn.edu/cheg/design/designequip.html
| Message 7
Subject: Polytanks leaching?
From: spettels 'at' newnorth.net
Date: Mon, 9 Apr 2001 13:28 +0100
Hi all!
We have 5,000,000 perch eggs coming in next week sometime. They will
be released into ponds once they are hatched and then retrieved. If we
have a good retrieval, we will need to get more tanks on line. We are
considering plastic tanks, however, a friend of ours recently heard on a
TV program that poly tanks leach. Has anyone else heard of this or had
any experience with this? What do they leach? Oils, chemicals? Will the
fish absorb it into their flesh? United States Plastic Corporation has
sheeting as well as plastic welders available. We are considering making
our own tanks, but would like to know if there is a problem first.
We are not using the S&S system yet, but we are talking with someone
who is selling his hydroponics set up (not an S&S system). Currently, we
are leasing a fish farm up in the Wisconsin Northwoods. We own a home on
5 1/2 acres, as well as, 40 acres up the road near Green Bay. That is
most likely where we would set up our system once we are ready.
Thanks for any input you may have,
Larry & Sarah
| Message 8
Subject: Used equipment?
From: spettels 'at' newnorth.net
Date: Mon, 9 Apr 2001 13:51 +0100
I can't remember exactly where I heard about used aquaculture equipment,
but I thought I would give this a try. We are looking for used
equipment. In particular, a dissecting microscope and a regular
laboratory microscope. Off list responses would be preferred unless it
would be beneficial info for the whole group.
Thanks,
Larry and Sarah
| Message 9
Subject: Re: New Guy with problem
From: S & S Aqua Farm
Date: Mon, 09 Apr 2001 13:58:28 -0500
At 07:47 PM 04/05/2001 -0500, Bruce wrote:
> Both Steves You need to install a clarifier in line between the fish
>tanks and the grow beds to keep the solid fish waste and unused food
>from plugging up your beds or that problem will recur regularly .
Bruce - We've not ever used a clarifier in our system. Perhaps the fish
problem was brought in from an outside source.
Steve wrote later with more details:
>I have some gold fish since early this winter. diden't have any proble
untill just about a month ago. It is not bad just one fish at a time seems
like. I always remove the fish. I have put in some channel cat, because I
diden't want to go with talipia untill I had all the bugs worked out.
Steve, where did the channel cat come from? Is it possible they brought
some disease with them that didn't bother them, but is causing problems for
your goldfish? The potential resistance to fish "illnesses" is one of the
reasons we chose tilapia in the first place. Maybe it's time to switch!
Paula
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
| Message 10
Subject: Re: Grow Bed Media
From: Ronald Polka
Date: Mon, 09 Apr 2001 14:33:51 -0600
At 03:58 AM 4/8/2001 +0100, you wrote:
>Hi,
> I am new to the group and have just started to set up my S&S style system.
>I am currently building a trial node.
>
>I am aiming to use local materials wherever possible. I plan to use gravel
>obtained
>from our local river as a growing medium. It will be sieved to get an even
>pea-gravel size.
>
>I was wondering if any body has had experience using gravel of Volcanic
>origins as a
>growing medium.
SNIP
Steve
I haven't used volcanic gravel as a growing medium per se in an
aquaponics system but have had good results with it as an artificial
wetland in a recirculating aquaculture system. One system that I ran for 6
years used two wetlands, one nitrification in the recirc loop and one for
denitrification in the waste water stream. Both wetlands are planted in
canna lilies that are the biggest and healthiest that I have ever seen, 7 -
8 feet high by midsummer. As you mentioned the honeycombed structure of the
volcanic rock provides ample surface area for the nitrosomonas and
nitrobacter bacteria to colonize. I have used two sizes of volcanic rock
large (1 1/2 to 3") in the nitrification wetland where the detention time
is short (3 hours). The denitrification wetland uses small gravel (about
1/2") and has a 4 to 5 day detention time for waste water treatment prior
to discharge. The small rock is pretty easy to work but the large rock
another matter entirely. The large rock is very hard to shovel and would
not be a good choice where one has to work the medium, plus it only seems
to work well with plants that have large root systems. I used to have other
plants in the wetlands such as Louisiana flag and bulrush but gave up on
them due to ferocious depredation by jackrabbits, fortunately they don't
care much for canna lilies.
Treatment prior to use depends on the source and the amount that
you are working with. Washing is helpful but a lot of work. Sterilization
is another matter that is up for debate. I guess a lot depends on the
conditions of the quarry where the rock comes from. The volcanic rock that
I used was bone dry and very dusty. I didn't even consider washing or
sterilization prior to use. There was too much to deal with, it was not
possible logistically. My only washing was prior to startup I ran water
through the finished wetland until the discharge was relatively clear.
If you operate a system with a heavy stocking density than you
will find a clarifier or settling tank essential. Otherwise solids entering
the gravel bed will fill the void space and increase you biological oxygen
demand (BOD) on the system. This will lower your DO in the bed and degrade
system performance substantially. I managed to clog my nitrification
wetland regularly during the time that I spent in fine tuning my settling
tank baffles. The nearly neutral buoyancy of tilapia feces can make it a
little tricky. The system should be designed so the solid wastes can be
discharged from the system on a regular basis, such as daily.
Ron Polka
Southwest Technology Development Institute
New Mexico State University
Box 30001, Dept 3SOL
Las Cruces, NM 88003
rpolka 'at' nmsu.edu
| Message 11
Subject: RE: Grow Bed Media
From: "Hurst, Steve ( China)"
Date: Mon, 9 Apr 2001 23:46:39 +0100
Thanks Mark,
I guess the Black Plastic drum is to soak up as much heat as possible.
After reading Ted 'at' s reply I was going to lay it out on the Highways,
and dry it like they dry the rice.
The problem with that is the local people think I am crazy anyway,
treating Lahar like rice would probably have been the last straw
and got me certified !
Should have another couple of months clear before rainy season starts.
Steve H
-----Original Message-----
From: Mark_Brotman 'at' kinetico.com [mailto:Mark_Brotman 'at' kinetico.com]
Sent: 09 April 2001 20:13
To: aquaponics 'at' townsqr.com
Subject: Re: Grow Bed Media
Steve,
A good way to sterilize soil in the tropics is to put it into a (clean)
black plastic drum, cover and put it on it's side. Leave it a sunny spot
for about a week, depending on the clouds and rain. Roll once a day to
mix. I bet this would work for your lava-type rocks well, as long as we're
not into your rainy season.
Mark
| Message 12
Subject: RE: Grow Bed Media
From: "Hurst, Steve ( China)"
Date: Tue, 10 Apr 2001 00:43:30 +0100
Ron,
Thats given me a lot to think about. I beleive all of your
experiences are going to be relevent to what I am planning on
doing.
One advantage here are the low labour costs. I have to have the
Lahar Sieved anyway,( all done by hand ) as this is how we obtain
our building sand. The rejected gravel is usually thrown away.
I just added an additional sieving process to get the size of
gravel I needed.
I particularly want to sanitise the gravel on this first trial node,
if only to try and not introduce any more variables, until I learn
how the system responds.
Reading the posts over the last week I was undecided as to whether
I would install a clarifier in this first system or not.
Your note ( below) leads me to beleive that the need for a clarifier
may depend on the type of grow-bed media you are using.
It looks like it could be essential for my Volcanic Lahar Material.
Thanks, your reply answered several questions I hadn 'at' t asked yet !
Steve H
> If you operate a system with a heavy stocking density than you
>will find a clarifier or settling tank essential. Otherwise solids entering
>the gravel bed will fill the void space and increase you biological oxygen
>demand (BOD) on the system. This will lower your DO in the bed and degrade
>system performance substantially. I managed to clog my nitrification
>wetland regularly during the time that I spent in fine tuning my settling
>tank baffles. The nearly neutral buoyancy of tilapia feces can make it a
>little tricky. The system should be designed so the solid wastes can be
>discharged from the system on a regular basis, such as daily.
SNIP
| Message 13
Subject: Cleaning Grow Beds in S&S system was: Steve, change your underwear!!
From: Bill Patrick
Date: Mon, 09 Apr 2001 19:58:17 -0400
Is this always the case for the S&S system? Or is Steve's system just
not "tuned in" yet? Not using a sludge collection (settling) tank is
one of the distinguishing feature of the S&S system. It has been my
understanding that pumping the solids into the grow beds made more
nutrients available to the plants as the solids were decomposed in the
beds and the solids then just sort of took care of themselves. If the
beds need to be cleaned, how often should we plan on doing this?
Thanks,
Bill Patrick
> I spent about 6 hours cleaning "unbelievable sludge" from the growbeds.
>
> Since that day, which is now almost 2 weeks ago, I have not made a water
> change, my nitrate/nitrite level is way down, my DO is way up, my water
> clarity is unbelievable. It (the water) is that healthy "tea brown" which
> Dr. J. refers to. The fish are eating like never before. My facility smells
> better. The tomatos that I could never get to grow are growing. The lettuce
> seeds that I planted 3 days ago are sprouting. (I continue to be amazed!!)
>
> SO THIS IS, NO ONE TOLD ME TO DO THIS!
>
> So, the S&S system works beautifully. You just have to keep it clean.(Kind
> of a "no brainer". But, if you don't know this, then you can have problems
> that will drive you crazy. I know they did to me.)
>
> Steve
| Message 14
Subject: Re: Cleaning Grow Beds in S&S system was: Steve, change your underwear!!
From: "TGTX"
Date: Mon, 9 Apr 2001 21:08:34 -0500
Bill,
The answer to your VERY insightful question, at the risk of my sounding like
an attorney, "depends". There are a number of sources within the system
that generate what we are loosely....perhaps Too Loosely....(wasn't he a
French painter?) calling sludge. Some sludge can be decomposed and
assimilated, but some kinds of sludge are tougher than other types. That
might be the title of my next album....."Tough Sludge, One Heart, Let's Get
Together and I'll Feel All Right" (apologies to Bob M.)
The fish feed itself may have "refractory" materials incorporated into the
formula, such as bentonite clay, or lignins, which are used as binders to
hold the feed pellet together in the water column until the fish can ingest
it..... and these binders, as I understand it, can also help to increase the
particle size of the feces, being relatively effective in performing the
same particle binding work throughout the passage of the feed through the
fish's gut.. thus increasing ability to sediment particulates
out....200 microns and bigger....or within that range... is a good thing to
shoot for in excreted fish feces solids cause it helps in recirc
systems....This is my reading of the literature I am familiar with.
But what do I know?
So, if your feed has these refractory binders in it, you may experience more
of this muddy sludge accumulation over time. Not much you can do other than
flush it out of the grow bed by having a separate flush line from the grow
bed that does not return that accumulating problem material back to the
fish tank...are you with me?
"Refractory" means relatively resistant to breakdown and
decompostion...there are feed binders that are less refractory, that is,
more prone to breaking down biologically, than other binders. I will stop
there on that particular subject, cause I am getting into STATE SECRET
territory ;-).
If the pore size of the growth media is TOOtsSMALL (Not a French Painter,
but perhaps a Reggae Artist), one may find that the sludge is captured and
not accessible to high oxygen attack from the ebb and flow system of
repetitive flooding and aeration, and the subsequent organic carbon
decompostion due to high oxygen "aquatic aerobic composting processes", and
thus, it accumulates. So, if the pore space of the growing media is too
small, sludge can build up. Surface tension of water itself, and the
sticky-ness of the biofilm come into play here on scales of typical pore
sizes.
On the other hand, if the pore space is too big, suspended solids can
readily pass through the system without some of them being captured onto the
surface area of the gravel....this has to do with a concept common to gas
chromatography, known as mean free path.....but.....if there is an actively
growing "series" of plants along a long biofilter path, then the roots
themselves can act in bio-chaotic ways as "the difference" between the big
pores of the gravel and the sometimes too small pores of the root
hairs.....Root hairs and root vascular systems are optimally designed, by
you know Who, me thinks, to occupy the pores of the substrate that they are
growing in. I am of the opinion that pore size in the growing media should
have a fairly narrow "optimal" range which balances aeration, hydraulics,
and filtration toward maximum decomposition of non-refractory solids.
Other sources of sludge build-up have to do with surface algae growing on
the surface of the gravel when plants do not shade the surface sufficiently.
There is a feedback loop here that is very interesting. If a region of the
surface of the pea gravel grow bed is not shaded quickly.....by rapid
germination of plants....and this germination is inhibited due to pooling of
the water on the surface of the gravel...which is in turn due to local
excesses of solids pumped to the gravel from the fish tank...then you can
get a runaway effect if you don't come in and disrupt the surface
"biocrust"and maintain the highly porous nature of the gravel as the design
is intended.... .
Let me re-state that. If solids are allowed to accumulate in local zones on
the surface of the grow bed... now this is right on the surface, you see,
where the surface tension of water comes into play pretty heavily....you
see. you will get localized pooling of water which results in the
water taking longer to dissipate that on average, and which will, over the
course of a few days, inhibit the germination and rapid growth of seeds sown
directly on that particular area...see? And then you can have an
accumulation effect. The take home message is to churn up the gravel and
break the "biocrusts" as often as is neccesary. Maintain the water
distribution pipes and the position of those pipes on the grow beds, so that
solids are not overly clogging the gravel pores in certain areas of the grow
beds. Don't overfeed the fish. Maintain a good ratio of fish and fish feed
and plants to gravel volume. There are all kinds of factors to optimize and
play with until you hit the "sweet spot".
You may have to flush the grow beds a few times if you accumulate solids too
much....if your system dimensions.....the relative volumes....the fish
biomass...the plant areas....the feed rates...the pumping rates....etc....
are set and fixed, you may have to continually or periodically do the solids
flush thing. If you can vary these and still operate things the way you
like, then there is the adventureThis is not readily described before
hand in this format. I advise you watch and take care and operate it until
it gets good to you and then you start leaning into it like riding a Heart
of Gold Motorcycle up the rocky, switch back road to Heaven.
Joy.
Ted.
(Just now harvesting dozens of vigorous "Yellow Roses of Texas" from the
flower beds this spring....they are luminous as the poets say....and
beautiful beyond words...wish I could share them with you all...)
| Message 15
Subject: Re: Polytanks leaching?
From: S & S Aqua Farm
Date: Mon, 09 Apr 2001 21:39:35 -0500
At 01:28 PM 04/09/2001 +0100, you wrote:
>Hi all!
> We have 5,000,000 perch eggs coming in next week sometime. They will
>be released into ponds once they are hatched and then retrieved. If we
>have a good retrieval, we will need to get more tanks on line. We are
>considering plastic tanks, however, a friend of ours recently heard on a
>TV program that poly tanks leach. Has anyone else heard of this or had
>any experience with this? What do they leach? Oils, chemicals? Will the
>fish absorb it into their flesh? United States Plastic Corporation has
>sheeting as well as plastic welders available. We are considering making
>our own tanks, but would like to know if there is a problem first.
Without more specific details on the program, it's hard to tell what the
main problem was, or what type of "poly" was involved. The tanks we use
(for grow-out) are also used in many outdoor aquaculture operations as
hatchery tanks.
I'll be interested in what response you get from other list members, and
also interested in your plans for 5,000,000 perch eggs! :>)
For more information on poly product safety from a manufacturer, you may
want to contact Tony or Dan at:
Polytank Corp.
62824 250th St.
Litchfield, MN 55355
800-328-7659
Web site: http://www.polydome.com/polytank.html
email
Paula
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
| Message 16
Subject: Re: Cleaning Grow Beds in S&S system was: Steve, change your
underwear!!
From: S & S Aqua Farm
Date: Mon, 09 Apr 2001 21:54:16 -0500
At 07:58 PM 04/09/2001 -0400, you wrote:
>Is this always the case for the S&S system? Or is Steve's system just
>not "tuned in" yet? Not using a sludge collection (settling) tank is
>one of the distinguishing feature of the S&S system. It has been my
>understanding that pumping the solids into the grow beds made more
>nutrients available to the plants as the solids were decomposed in the
>beds and the solids then just sort of took care of themselves. If the
>beds need to be cleaned, how often should we plan on doing this?
>
>Thanks,
>Bill Patrick
Bill - As I recall, Steve was raising tilapia already, then added growbed
filtration to his existing set-up. As he said, his is 90% our type of
system. As to what the other 10% is, I'm not certain.
One thing I would remind you of -- we do not gear our system for maximum
fish production. A greater percent of the profit comes from the
produce/plant side, so that is the system that gets the most attention.
Using mechanical filtration, solids removal, and water changes, you can grow
lots more pounds of fish per gallon than we do -- we just don't.
Steve said:
> Since that day, which is now almost 2 weeks ago, I have not made a water
> change, my nitrate/nitrite level is way down, my DO is way up, my water
> clarity is unbelievable. It (the water) is that healthy "tea brown" which
> Dr. J. refers to. The fish are eating like never before. My facility smells
> better. The tomatos that I could never get to grow are growing. The lettuce
> seeds that I planted 3 days ago are sprouting. (I continue to be amazed!!)
> So, the S&S system works beautifully. You just have to keep it clean.(Kind
> of a "no brainer". But, if you don't know this, then you can have problems
> that will drive you crazy. I know they did to me.)
I hope he'll pipe in, but he doesn't say he had to reinnoculate the beds,
change water again, nor did he say that he continues to drag sludge out of
the beds. It sounds as if the system was overloaded (overfeeding?) at one
point and just crashed. Once the cause of the poor balance was corrected,
the system balanced out properly.
We don't "clean" the beds, but we do loosen the gravel when we change crops,
and try to keep excess plant debris from the surface of the beds. A dead
leaf on top of a moist gravel surface will start some beautiful algae, but
it's really hard for seeds to sprout through a solid algae cover.
Paula
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
|
