TRICKLE TOWERS & “BAKKI” SHOWERS

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Transcript TRICKLE TOWERS & “BAKKI” SHOWERS

TRICKLE
TOWERS
& “BAKKI”
SHOWERS
• by Noel L Shaw
• AKCA Koi Health Advisor
• [email protected]
WHY WE DO IT
OVERVIEW
1. Bioconverter Basics
2. BioConverter Design
3. Water Flow
4. Oxygenation
5. The Ideal BioConverter
6. Things that can go wrong
7. Summary
1. BIOCONVERTER BASICS
The purpose of the BioConverter is to convert
nitrogenous waste (ammonia excreted through the
gills) to relatively harmless compounds via the
nitrite / nitrate cycle.
In addition, the ideal bioconverter will convert
organic (carbon containing) compounds in solid fish
waste to an oxidized state - ultimately carbon
dioxide - which will then gas off to the
atmosphere.
Its job is NOT to remove solid waste (fish or
otherwise) from the water.
Bioconverters work because of the actions of
hard working, middle class bacteria,
which, like koi, have basic needs:
a) A home (usable surface area):
- gravel
- matting
- ribbon
- beads
b) Food: exposure to nitrogenous & organic compounds
1) stuff in water
2) exposure to water
3) appropriate flow rate - fast vs slow
c) Oxygen: supplied by O2 dissolved in the water
2. BIOCONVERTER DESIGN
A) Pre-Filter:
Catches the big chunks to help avoid clogging
bioconverter media
- Settling chambers
- Coarse matting
- Should not be relied on for bioconversion
- Should be easy to clean / flush
The pre-filter is the first line of defense for the
bacteria in the bioconverter, to keep them from
being smothered in solids.
B) BioConverter Media:
Home, home on the range … Where the
Nitrosomonas and Nitrobacter (and Aeromonas)
play …
- Adequate total surface area?
- Flow capacity
- Maintenance of design flow - will media settle
together, plug easily, or clump?
- Contact time with water
- Biggest possible for space and budget
- No such thing as over - filtration
BIOCONVERTER TYPES
Bead Filter
Fluid Bed Filter
Matting Filter
Maximum O2
level possible:
Maximum O2
level possible:
Maximum O2
level possible:
9 ppm
9 ppm
9 ppm
The DO concentration for 100% air saturated water at sea level is 8.6
mg O2/L at 25°C (77°F) and increases to 14.6 mg O2/L at 0°C.
Moore, M.L. 1989. NALMS management guide for lakes and reservoirs. North American Lake Management Society,
P.O. Box 5443, Madison, WI, 53705-5443, USA (http://www.nalms.org).
OTHER
POSSIBILITIES …
Maximum O2
level possible:
9 ppm
AquaScapes type filtration
- gravel / rock surface area & matting
3. WATER FLOW
Flow rate:
Turnover time (all pond water passes through
bioconverter) of at least once per hour
General plumbing considerations:
- Pump size (design flow rate)
- Actual flow rate = design flow rate minus back
pressure due to height and back pressure due to
friction in plumbing, fittings, and other
restrictions
- Pipes never get bigger, they get smaller with
buildup
- Pressure of media (draw through or pressurized
filters and bioconverters)
Bioconverter plumbing
and flow considerations:
High flow rate is OK and even great if:
a) the water is clean and won’t plug up the front line
of the media, and
b) bacterial colonies won’t be mechanically knocked
off by excessive turbulence, and
c) there is a large frontal cross section of media
(water can flow through gently and equally as
opposed to being pushed through a small opening
through multiple layers)
Consider trying to push a certain volume of water
through a certain amount of filter media,
represented by the media filled cylinder, open at the
ends.
All of the water needs to go through the
first layer of media (shown in green). If it
plugs, all water flow ceases.
Now consider trying to push that same volume of
water through the same amount of filter media, but
the water is flowing through the sides.
The water has a much larger surface area to
spread out over as it passes through the
media.
This filter design will flow with less pressure,
and will be much more difficult to plug up.
4. OXYGENATION
Oxygen is our friend.
- Higher levels of oxygen can support higher
densities of bioconverter bacteria.
- Goal of water flow is O2 saturation at all levels of
pond activity (top, bottom, in bioconverter)
- Bioconverter bacteria, even more than koi, function
best at high O2 levels.
Oxygenation of pond water:
- Bring the water to the oxygen (“flooming”, streams)
- Bring the oxygen to the water (waterfalls, air
pumps, turbulence)
Water, when cold and highly tumbled, holds, at
best 9-10 ppm of dissolved oxygen.
Air, by contrast, holds about 21%
(210,000 ppm) oxygen.
If we can get the media (and thus the bacteria)
into the air, and still provide the bacteria with
food and moisture to do their duties (or is that
doodies?), they stand a much better chance of
being at O2 saturation, and their populations
and therefore productivity should be much
greater.
5. THE IDEAL BIOFILTER
What Kind Of Bio Converter
Enables Maximum Oxygenation;
Can Handle Huge Water Flows;
Has A Huge Media Surface
Area; Has Little Or No
Restriction; Has Rapid Biological
Start Up And Recovery; And
Will Not Go Septic After A Day
Without Water Flow?
Bakki Showers
“THE” Bakki Shower … $5000.00 ish
Trickle Towers
Shower Filter
Barrel basin
4” pond outlet to pre-filter
Ventilated “milk” crates
Pre-Filter
3” pump outlet to 2-2” valves
Cover (evaporation, shade, and splash)
Free flow water return
Four 1-1/2” spray bars per tray set
You’ll also need huge
plumbing, lots of space
above water line (this is a
gravity return system) , a
BAP (large pump), and ...
A means to hide the Shower Filter
This is a temporary pond, above
ground, built to avoid the trouble
and expense of dealing with a
built-in in a few years.
The filter cover is for water loss,
and does little to camouflage the
filter. The screen in front helps a
little.
Lava Rock Tray after six months
Spray Bar after six months
6. WHAT CAN GO WRONG....
Just kidding …
Potential Drawbacks
Shower Filters are large.
They are gravity return, so they need to be
above the water level of the pond.
They require massive water flow.
They splash a fair amount.
They lose water to evaporation.
They can cool the water too much in winter.
They are loud (a pleasant sort of loud).
Potential Solutions
Hide the Filters behind a screen or a faux
rock waterfall.
Use the gravity return to further direct
water flow in the pond.
Use large plumbing to flow huge water and
minimize friction and power losses.
Cover to minimize splashing, water loss, and
excessive cooling in winter.
Install an autofill.
Enjoy the extra water noises.
7. SUMMARY
Efficiency of oxygenation.
Great water movement.
Organics and nitrogens are broken
down very rapidly.
Cooling effect in summer.
Soothing effect on fish.
Except for “Bakki Shower”, each
pond / filter setup needs to be
specifically engineered.