Aquaculture facts

Aquacul­tu­re is com­pre­hen­ded as the bree­ding or cul­ti­va­ti­on of aqua­tic orga­nisms (ani­mals and/or plants), in which spe­ci­fic inter­ven­ti­ons during the upbrin­ging are being made. Such inter­ven­ti­ons are fee­ding, (re-)stocking the spe­ci­men on a regu­lar basis and all fur­ther inter­fe­ren­ces, which are neces­sa­ry to main­tain or increase the production.

The ear­ly begin­nings of aquacul­tu­re are dated way back in Chi­na around 500 B.C. Sin­ce then, this cul­ti­va­ti­on form has been a per­ma­nent food sup­p­ly for our socie­ty: in the anci­ent world the Romans main­ly cul­ti­va­ted clams, during the Midd­le Ages carps were held in ponds by monastic orders and sin­ce the 19^th hundreds it has been a way of kee­ping exo­tic fish in zoo­lo­gi­cal gar­dens in Euro­pe. Nowa­days modern aquacul­tu­re pro­ces­ses are hel­ping natu­ral aqua­tic popu­la­ti­ons to reco­ver and also pro­vi­de a much nee­ded sup­p­ly of high-qua­li­ty ani­mal pro­te­ins for the gro­wing world popu­la­ti­on. In 2016, every second eaten fish was held in an aquacul­tu­re farm.

The­re are many aspects to dif­fer aquacul­tu­re sys­tems; one way is to dif­fe­ren­tia­te the sys­tems regar­ding the water con­sump­ti­on and sto­cking den­si­ty, thus the weight of cul­tu­red orga­nism per cubic meter water volu­me (= kg/m³) – the­se opti­ons are cal­led exten­si­ve, semi-inten­si­ve or inten­si­ve aquacul­tu­re. Fur­ther­mo­re, it can vary in terms of fresh water or salt­wa­ter usa­ge as well as how the aquacul­tu­re sys­tem is inter­ac­ting with the sur­roun­ding eco­sys­tem. An open cul­ti­va­ti­on is in direct cont­act to the eco­sys­tem, whe­re­as a clo­sed one has bare­ly to no influence on the surrounding.

Con­ven­tio­nal open aquacul­tu­re sys­tems are ponds, floa­ting net cages or flow-through faci­li­ties. The impact the­se have on the envi­ron­ment can be very gra­ve: unea­ten feed and the pro­ducts of the meta­bo­lism excre­ted by the spe­ci­men (feces, car­bon dioxi­de) can be trans­por­ted into sur­roun­ded eco­sys­tems and dama­ge them, if the water and feed manage­ment is insufficient.

A pos­si­ble solu­ti­on the­r­e­fo­re is a clo­sed sys­tem (recir­cu­la­ting aquacul­tu­re sys­tem, abbr. RAS). A RAS by defi­ni­ti­on has a dai­ly water exch­an­ge rate below 10% of the who­le water volu­me of the faci­li­ty. The most modern RAS like the SEAWATER Cube even accom­plish a rate below 1%, hence a RAS is a near­ly com­ple­te­ly clo­sed sys­tem. The requi­red water qua­li­ty is rea­li­zed through the usa­ge of mul­ti­ple phy­si­cal and bio­lo­gi­cal water tre­at­ment pro­ces­ses. That is the reason for not nee­ding a con­nec­tion to natu­ral waters and the loca­ti­on of the faci­li­ty can be cho­sen wit­hout taking this into consideration.

Ano­ther advan­ta­ge is, that important para­me­ters like tem­pe­ra­tu­re, sali­ni­ty, pH, par­ti­cu­la­te mat­ter, germs or the con­cen­tra­ti­ons of oxy­gen and car­bon dioxi­de can be effec­tively con­trol­led and with it the cul­ti­va­ti­on con­di­ti­ons can be opti­mi­zed con­cer­ning the wel­fa­re of the ani­mals. Com­pared to an open sys­tem, the impacts on the envi­ron­ment are simul­ta­neous­ly lowe­red upon a minimum.

The SEAWATER Cube and its tre­at­ment pro­ces­ses are not desi­gned by the tole­ra­ble boun­da­ries of the ani­mals, but by main­tai­ning a living envi­ron­ment at its best while pro­vi­ding the neces­sa­ry salt­wa­ter quality.