A RAS is perfect solution for fish farming on land, we manufacture aeration tubes to help this system to perform better. With our tubes you can attain a better rate of DO in a short span of time. For more information visit: http://www.airoxitube.com/aeration-tubing-products/airoxi-tubes/

1. Introduction to Recirculating Aeration
System (RAS)

2. What is Recirculation
Aeration System
(RAS)
Recirculating aquaculture
systems (RAS) are used
in home aquaria and
for fish production
where water exchange is
limited and the use of bio
filtration is required to
reduce ammonia toxicity.

3. Benefit of RAS
• Ability to reduce the need of fresh water.
• Ability to reduce the need of clean water.
• Maintaining healthy environment for fish.

4. RAS Process
Biofilteration
Solids
removal
Oxygenation
pH Control Biosecurity

5. Biofilteration
All RAS relies
on biofiltration to
convert ammonia
(NH4
+ and NH3) excreted
by the fish into nitrate.
1
A biofilter provides a
substrate for the bacterial
community, which results
in thick biofilm growing
within the filter. Water is
pumped through the filter,
and ammonia is utilized by
the bacteria for energy.
2
Stable environmental
conditions and regular
maintenance are required
to ensure the biofilter is
operating efficiently.
3

6. Solid Removal
In addition to treating the liquid waste
excreted by fish the solid waste must
also be treated, this is done by
concentrating and flushing the solids out
of the system. Removing solids reduces
bacteria growth, oxygen demand, and
the proliferation of disease.
1
Typical RAS solids removal involves a
sand filter or particle filter where solids
become lodged and can be periodically
back flushed out of the filter.
2

7. Oxygenation
Reoxygenating the system
water is a crucial part to
obtaining high production
densities.
1
Fish require oxygen to
metabolize food and grow,
as do bacteria communities
in the biofilter. Dissolved
oxygen levels can be
increased through two
methods aeration and oxyg
enation.
2
Airoxi Tube provides tube
which help RAS to run
efficiently and increase
oxygen.
3

8. pH Control
In all RAS pHmust be carefully
monitored and controlled. The
first step of nitrification in the
biofilter consumes alkalinity and
lowers the pH of the system.
1
Keeping the pH in a suitable
range (5.0-9.0 for freshwater
systems) is crucial to maintain
the health of both the fish and
biofilter.
2

9. Biosecurity
Disease outbreaks occur more readily
when dealing with the high fish stocking
densities typically employed in intensive
RAS.
1
Outbreaks can be reduced by operating
multiple independent systems with the
same building and isolating water to
water contact between systems by
cleaning equipment and personnel that
move between systems.
2

10. Our Products
AirOxi Tubes
AirOxi Tube Self Sinking Aeration Tube
AirOxi Tube Grid
AirOxi Floating Diffuser Grid
For more information visit:
http://www.airoxitube.com/aeration-tubing-
products/

11. Contact Us
http://www.airoxitube.com/
https://www.facebook.com/airoxitube
https://twitter.com/airoxitube
+91 - 7285017087

12. Thank You