Showing posts with label aquaculture. Show all posts
Showing posts with label aquaculture. Show all posts

Egg incubation / hatching substrate

Use of Enkaflex® as an egg incubation/hatching substrate within IAT “Bluewater” recirculation systems
• Used from post eyed to first feeding only.

• In 5m diameter fish tanks, used as follows (method is adaptable!).

• 6 ‘spokes’ radiating from tank centre, approx. 1m wide (roll width) by 2m long.

• Spokes laid ‘smooth side down’ and weighted with clean stones.

• Each spoke overlaid with two stainless steel ‘Marr Tray’ Grids, with ‘raising bolts’ in corners to hold MTG approx. 10mm off surface of Enkaflex®.

• Alternative egg grids could be used BUT avoid other metals (e.g. aluminium) within recirculation system, and ensure 10mm gap between grid and substrate.

• Water level in tank to apprx 10-20mm above egg grids. Very slow flow rate set (to avoid washing eggs from grids).

• Approx. 200-220k eyed ova added per tank, by pouring from jug (33k-36k per spoke).

• Nominally 20,000 per m2.

• Check in tank oxygen levels are competent!

• Post hatch, remove MTG or its equivalent. Clean and store.

• Examine alevins at routine intervals to establish readiness to first feed.

• At appropriate time, enter tank and gently remove Enkaflex® spokes by lifting from one corner. Allow alevins time to escape.

• To clean Enkaflex® post use: ‘Hang over washing line and pressure wash to clean’.

• Significant improvements in survival and first feeder weights (up 25%) are reported. Vast area of suitable space for alevins to gain surface contact. No yolk sac pinching at all. reduced stress and reduced need for movement must be beneficial.

OVAMAT in spawning tanks

Geosynthetics also helps in fishing industry, in fisheries.

OVAMAT - The economical way to increase the egg holding capacity of spawning tanks
OVAMAT introduces a random 3D mono filament structure throughout the bottom 180mm of the spawning tank creating a significant area of additional space within the existing facilities thus increasing its egg holding capacity. When laid in the bottom of the spawning tank OVAMAT provides an extensive open network of nylon threads onto which the ova can attach themselves. OVAMAT acts as a substitute for the three-dimensional features normally found in the environment of a river or stream. Actually Ovamat is also a type of 3 dimensional synthetic product which is similar to Enkamat.
• This hatchery matting provides up to 30% more egg holding capacity in existing tanks.

• Density, its specific gravity exceeds 1.0. It will not float and lies evenly on the bottom.

• Easy to clean and disinfect. Can be used time and time again.

• The open structure of the material presents no hazard to aleven.

• A tough mono-filament three dimensional polyamide matting with 90% open volume.

• Resistant to all chemicals found in fresh or river water UV stable.

• Totally inert and harmless to the environment. Of no nutritive value.

• Flexible and light, it can be cut to size with scissors or sharp blade.
Related Posts Plugin for WordPress, Blogger...