Bol. Inst. Pesca, São Paulo, 44(vol. esp.): 64 - 73, 2017
Doi: 10.20950/1678-2305.2017.64.73
LETTUCE PRODUCTION IN AQUAPONIC AND BIOFLOC SYSTEMS WITH SILVER
CATFISH Rhamdia quelen
Andréa Ferretto da ROCHA
1
; Mario Luis BIAZZETTI Filho
2
; Marcia Regina STECH
1
;
Raquel Paz da SILVA
3
ABSTRACT
Aquaponic and biofloc systems have advantages when compared to conventional food production,
but studies that associate both systems are incipient. The aim of this study was to evaluate the
development of Lactuca sativa in hydroponic and aquaponic systems (with Rhamdia quelen) with or
without bioflocs using minimal infrastructure. Hydroponic (H-system), aquaponic (Aqua), and
aquaponics with bioflocs (Aqua-BF) were evaluated in a randomized design. It did not use a
greenhouse, and it used a single tank to produce vegetables and fish together. The stocking density
of lettuce was 20 plants m
-2
. A total of 168 R. quelen juveniles were used to Aqua and Aqua-BF.
Total ammonia, nitrite, and turbidity of the water were higher to Aqua-BF than H-system and
Aqua. Lettuces were significantly more productive in Aqua and Aqua-BF than H-system. There
were no differences between Aqua and Aqua-BF for the parameters lettuce production and fish
performance. Under the conditions of this study, it was possible to conclude that aquaponic
farmers can use silver catfish, and aquaponic systems with and without bioflocs can improve the
lettuce produce. The use of bioflocs in the aquaponic system may improve the productivity but
needs a better study to optimize and simplify this technology.
Keywords: green vegetable; hydroponic; multitrophic system
PRODUÇÃO DE ALFACE EM SISTEMAS DE AQUAPONIA E BIOFLOCOS COM JUNDIÁ
Rhamdia quelen
RESUMO
Aquaponia e sistema de bioflocos possuem vantagens quando comparados com sistemas
convencionais de produção de alimentos, mas estudos que associam esses sistemas são incipientes.
O objetivo deste estudo foi avaliar o desenvolvimento de Lactuca sativa em sistemas hidropônicos e
aquapônicos (com Rhamdia quelen) com ou sem bioflocos utilizando mínima infraestrutura.
Hidroponia (H-system), aquaponia (Aqua) e aquaponia com bioflocos (Aqua-BF) foram avaliados
em delineamento inteiramente casualizado. A alface e os peixes foram produzidos juntos em uma
única caixa, sem o uso de estufa. Foram utilizadas 20 plantas m
-2
. Foram utilizados 168 juvenis de
jundiás para Aqua e Aqua-BF. Amônia total, nitrito e a turbidez da água foram maiores para
Aqua-BF que para o H-system e Aqua. A produção de alface foi significativamente maior em Aqua
e Aqua-BF dos que em H-system. Não houve diferenças entre Aqua e Aqua-BF para produção de
alface e desempenho dos peixes. Sob as condições deste estudo, foi possível concluir que o jundiá
pode ser usado em sistemas aquapônicos com ou sem bioflocos e que ambos os sistemas podem
melhorar a produção de alface. O uso de Aqua-BF pode melhorar a produtividade, mas precisa de
um melhor estudo para otimizar e simplificar o uso desta tecnologia.
Palavras-chave: vegetais; hidroponia; sistema multitrófico
Original Article/Artigo Científico: Recebido em 11/11/2016 Aprovado em 03/07/2017
1
Research Center Herman Kleerekoper, State Foundation for Agricultural and Livestock Research (Fepagro), Fepagro
Aquaculture & Fishing. BR 101, km 53 - Post office box 03 - Terra de Areia CEP: 95535-000 RS Brazil. e-mail:
andreafdarocha@hotmail.com (corresponding author); marciareginastech@gmail.com
2
Federal University of Rio Grande do Sul (UFRGS). RS-030, km 92, n.11.700 CEP: 95590-000 Tramandaí RS Brazil.
e-mail: biazzetti@live.com
3
State Foundation for Agricultural and Livestock Research (Fepagro), Fepagro North Coast. RS 484, km 05 CEP: 95530-000
Maquiné RS Brazil. e-mail: ranitapaz1970@gmail.com
Lettuce production in aquaponic and biofloc systems with silver … 65
Bol. Inst. Pesca, São Paulo, 44(vol. esp.): 64 - 73, 2017
INTRODUCTION
The lettuce Lactuca sativa is cultivated
throughout Brazil, especially by family farms
(SOARES et al., 2015). Lettuce is globally grown
for fresh consumption in salads, and it is used on
a large scale in hydroponics, called NFT (Nutrient
Film Technique) (CARVALHO et al., 2015). When
producing vegetables, traditional hydroponics
systems rely on fertilizer solutions to meet the
nutritional needs of plants that grow in water.
The use of green vegetables is recommended
for aquaponics since it tolerates high levels of
water in their roots and the significant variations
in the levels of nutrients that are dissolved in the
nutrient solution without symptoms of nutritional
deficiency (EFFENDI et al., 2016). The aquaponic
system use for plant growth the available fish
water that is rich in fish waste as nutrients, which
become available through the microbiological
activities that occur in the aquatic environment
(MARTINS et al., 2010; GODDEK et al., 2015). The
aquaponics system has advantages when compared
to conventional agricultural ecosystems. For
example, aquaponic is more efficient in the use of
water and area and waste from other cultures;
higher productivity; lower cost of inputs and
labor; greater biosafety contribution; less need
for monitoring water quality; easy system
management (RAKOCY et al., 2006; GRABER
and JUNGE, 2009).
The aquaponic has been predominantly
spread throughout the world through home-
scale producers (HUNDLEY et al., 2013). Most
hydroponics operations are in controlled
environment facilities, but a recent international
survey shows that just 47% of aquaponic systems
were outdoors, 46% were in greenhouses or
high tunnels, 28% were inside buildings, and 3%
were on rooftops (LOVE et al., 2014). Studies to
meet the first steps of amateur producers in cities
need to be produced.
In shrimp and fish farms the bioflocs system
gets the better purpose of water, through the
benefit of aerobic heterotrophic culture system
and minimal water exchange. In this system, the
nitrogenous compounds presented in the water
are converted into bacterial biomass, called
bioflocs, from the incorporation of ammonia by
heterotrophic bacteria in the environment, acting
as a biofilter (AVNIMELECH, 2007).
Aquaponic and biofloc systems are considered
promising and an emerging approach, which
combines intensive production with waste
recycling and water conservation (KLINGER and
NAYLOR, 2012). Albeit studies associate that
aquaponic and biofloc systems are incipient, the
use of bioflocs in the aquaponic system may
provide ideal conditions for bacteria to control
water quality that will promote the recycling of
nutrients in the water (AVNIMELECH, 2007).
FAO (2016) points out that the in the last five
decades the fish production has been growing at a
constant rate, being that the global consumption
per capita of fish has increased. Therefore, in the
future, the agriculture sector will need to produce
more with less. The uses of biofloc and
aquaponics systems are helping in the increase of
aquaculture production. Starting from the
elements of efficient resource use by integrating
food productions systems and reducing inputs
and waste, aquaponics systems can become an
additional means to tackle the global challenge of
food supply (FAO, 2016). WASIELESKY et al.
(2006) mention the advantages of the bioflocs
system, as there is zero water exchange, an
increase of density and biosafety, reduction of the
amount of protein in the rations and minimal
environmental impact.
The silver catfish (Rhamdia quelen) is
distributed in Central and South America, and it
is found in rivers, lakes, and streams. This species
is adapted to different methods of rearing
(BALDISSEROTTO and RADÜNZ NETO, 2004),
and its commercial production has been
encouraged in Southern Brazil.
Until this moment, there is no study about
lettuce crop in an aquaponics system in
association with biofloc and silver catfish. This
study presented preliminary results of the
production of lettuce in floating raft system
without the use of solids separator and using
the same tank to produce vegetables and fish, as
well without a greenhouse, outside and in semi-
temperate climate. As well, it evaluated the
development of L. sativa in hydroponic and
aquaponic systems (with R. quelen) with and
without bioflocs using minimum infrastructure.