What is the effect on the oxygen level?
Like any net, the oxygen level in the net is lower than the oxygen level outside the net. The big advantage of Thorn-D® is that this oxygen level remains on the same, stable level whereas toxic antifouling causes a decrease by time due to blocking of the meshes.
The circumstances in our country are different to the circumstances in Turkey
The reason we chose for introduction in Turkey is the whole year around heavy fouling so an ideal test location. If we have success in Turkey, we certainly do not expect to any problem/fouling in cold water. The amount of sunlight in Turkey is higher which means more heavy fouling. Fouling species are divided in 8 categories which occur in any kind of water, they are all represented in Turkey.
What is the influence of Thorn-D on the net?
Very positive. First of all, the yarn/twine is protected by the adhesive. Secondly ,the breaking load of a Nylon net increases up to 40% and Dyneema up to 20% depending on the circumstances.
How do you know Thorn-D last for 5 years?
As the working principle of Thorn-D® is not based on leaching like copper antifouling, the product does not loose its activity. The fibres remain on the surface and keep their physical antifouling performance for the lifetime of the net.
What fibers do you use ?
Nylon fibers
Will the adhesive “survive” in the water?
Yes due to the use of 2-components adhesive. This has been tested intensively.
Is the adhesive harmful?
No. The adhesive we use is a environmental friendly water based acrylic.
What is the effect on fish stress levels?
Reduced stress due to less changing of the net in case Thorn-D is used. Less changing also means less chance of contamination.
Can fish eat the material?
During a period of 3 years of testing with a Thorn-D® net containing seabream, no biting has been seen. An independent report from the Aegean University shows no fibres in the intestines of the fish nor any chemical substances.
What happens with the fish if they bite in Thorn-D?
During a period of 3 years of testing with a Thorn-D® net containing seabream, no biting has been seen. An independent report from the Aegean University shows no fibres in the intestines of the fish nor any chemical substances. Unravelling of a ordinary net due to biting causes loose/broken filaments which can be swallowed by the fish. This can lead to death of the fish. With Thorn-D, the glue firmly attaches the filaments to each other and therefore no unravelling will happen.
Has Thorn-D effect on the skin of the fish due to rubbing?
No, Thorn-D is a soft fibre therefore no damage will occur. Copper antifouling is a harder surface and can contain hard fouling which might cause damage.
Will this (wider meshes) effect the change for escapes or extra biting?
Thorn-D is very unattractive to bite. During three years of testing of a Thorn-D®-net with seabream, no biting has been observed. At the same period, no escapes has occurred.
Will enough fresh water flow in the cage as the opening will be smaller due to Thorn-D?
We will increase slightly the mesh-size to obtain the same original mesh size and therefore the flow will remain the same.
Can you advice on the weight we should use?
Yes, we need the local current data to calculate.
What about drag resistance?
Yes, Thorn-D has a slightly more drag resistance. In case it is an issue, this can be solved by using more balancing weight. Please visit the download section for more information regarding drag-resistance which has been tested at Sintef.
Is Thorn-D washable?
Yes. Tumble washing machines can be used as well as a high pressure hose (depending on the pressure, please check on a small piece)
How to deploy the Thorn-D®-net underwater?
Thorn-D is lighter then cupper coated net. In case it is necessary we recommend to increase the weight attached. During deployment, local support can be provided.
Is Thorn-D bulky in transport?
The volume is 2-times bigger, however it is not heavier. Indeed you need more space while transporting the Thorn-D®-net.