Subject: Fecal Coliform in Fish Hatchery wastewater

From: [email-masked]
Date: 27 Mar 1996 18:15:57 GMT

Hi all,

I am doing a study on the presence of Fecal Coliform bacteria in the wastewater of  fish farms.
 I am looking for any material that indicates wether this is due to domestic waste in groundwater 
entering the waste effluentor if it is native to fish hatchery wastewater.

If anyone can suggest sources of information I would greatly appreciate it.

Thanks.
     Steve Isakson  email:[email-masked]

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From: [email-masked] (Mike Christensen ENGINEERING DEPARTMENT)
Date: 28 Mar 1996 08:27:54 -0600

[email-masked] wrote:
: Hi all,

: I am doing a study on the presence of Fecal Coliform bacteria in the wastewater of  fish farms.
:  I am looking for any material that indicates wether this is due to domestic waste in groundwater 
: entering the waste effluentor if it is native to fish hatchery wastewater.

: If anyone can suggest sources of information I would greatly appreciate it.

: Thanks.
:      Steve Isakson  email:[email-masked]

I don't know right off hand any references, but probably any one of the 
general purpose aquaculture books published by Elsevier Publishing would 
have the info.  However, just fyi, fecal coliforms are not produced by 
fish, only by mammals.  But just to remember that means any mammal, 
including small rodents running around a farm, or cattle, or dogs, or 
etc., etc.  The primary problems with fish waste discharge are nutrient 
discharges resulting in eutrophication of receiving streams (eg 
phosphorous, ammonia, nitrite, nitrate).  We are curently working or 
research to this effect, the use of recirculating systems to reduce 
discharge and the use of constructed wetlands to treat the waste prior to 
discharge.

Hope that helps,
Mike

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From: [email-masked](brett rowley)
Date: 29 Mar 1996 01:55:12 GMT

>     Steve Isakson  email:[email-masked]
Steve,

Be very careful in doing your identification of fecal coliforms.  I'm
no expert, but I know of at least one case where a similar bacteria was
misidentified in an aquaculture facility waste stream.  Fish don't
produce fecal coliforms, mammals do.  Dilute fish waste is fairly
benign.  In fact many aquaculture facilities (like the one I work at)
impound nutrient rich, silt laden water and discharge, clear, clean
water.  In many cases, fish wastes can be concentrated and treated
seperately from the general discharge.  Compared to most traditional
agricultural (non point) discharges, as well as industrial and
residential (point) discharges, fish water is very clean indeed, in
fact, fish are living in it.  Regulators give fish culture facilities a
lot of attention to appear that they are actually doing something. 
Meanwhile, agricultural, industrial, and residential discharges are
largely ignored, or rubber stamped.  Of course most fish farmers
haven't much money to spread around.

As a science fair project, my 10 year old daughter and I tested ammonia
and nitrates at several locations in two streams near our home.  One
has several fish farms located along it, the other has no fish farms,
but a waste treatment plant discharging treated residential wastes.  We
found nitrates and ammonia near zero along the stream with the fish
farms along it, but the other stream had readings above 100 ppm for
nitrates, and 0.5 ppm for ammonia near the treatment plant, and
detectable levels all the way to the coast, even after several other
streams entered it and diluted it.  We plan to look again during the
rice irrigation season to see how that affects our readings in the two
streams (both have lots of rice farms).

Brett Rowley
Fisheries Biologist
Great Lakes Sportfishing Resort and Koi Breeding Farm
West Columbia, Texas