Jared has tried to explain his
trickle filtering system to members of the turtle list in several posts. Jared
has written a short description for each picture featured below. Additional
pictures and descriptions will follow in the near future.:)
Please click on
the pictures if you would like to have a better view of each
- This picture
represents the beginning of a transition in filter design for a 180 gallon
brackish water tank. The salinity was maintained at roughly 1.012 and there
were approximately five sub adult malaclemys terrapin centrata in this
As it can be seen, there are three types of filtration:
- protein skimmer;
- external canister filter and;
- trickle filter.
The protein skimmer is a
standard air driven skimmer. The skimmer column is 4" in diameter, roughly 20"
high and there are four wood air blocks in it. The air pump is a Wisa model
200. The Wisa was chosen for its superior design and durability. Its PSI simply
cannot be matched by any of the less expensive plastic air pumps. The only
plastic air pump that comes close to the Wisa in quality is the Tetra Luft air
pump. At a fraction of the cost of the Wisa ($50 vs. $200) it is a very good
buy for the money. The only draw back is the noise - it is significantly louder
that the Wisa, and at maximum output, it can not be used on a set up that is in
a public area of the house. The water is pumped into the skimmer from a
submersible Eheim 1260 pump that is in the tank.
The canister filter is a Eheim
2260. It uses the same Eheim 1060 pump that was discussed in one of the earlier
pictures. While this filter is definitely superior by function and design to
virtually any other canister filter, its' size makes it awkward to clean,
particularly when there are heavy bio-loads, which will necessitate cleaning on
a more frequent basis. The bio-media that is inside of it is made by Eheim and
is a highly porous, large surface area type of synthetic stone. The problem is
that is becomes easily clogged which therefore reduces the flow of water
through the filter.
I substituted this media with
larger pieces of lava rock, which still did not improve matters much as the
lava rock also became clogged with detritus, thereby raising nitrate and
phosphate levels in the tank. As the next picture demonstrates, the canister
filter was removed.
The third type of filtration is
a over the tank trickle filter. It works exactly the same as the one described
in one of the pictures below. It too uses an Eheim 1060 water pump, mounted
externally, which can be seen in the picture.
- This picture
represents the final transition on this 180 gallon tank. It is an end shot
showing the protein skimmer, and large custom made hang on pre-filter. Within
the pre-filter, there are roughly 2 gallons of flex-rings, increasing the
surface area of the bio-media.
The blue Rubbermaid storage bin
that is depicted in this picture, and in the following picture, is used as a
top sump to compensate for evaporation. The frontal view of the 180 gallon tank
shows the bin connected to a small section of reverse osmosis tubing (from an
RO unit - though any kind of thin tubing will work). There is a small nipple
that has been screwed into place at the bottom of storage bin. Silicone has
been added to help ensure a water proof seal.
The other end of the tubing is
connected to a nipple that comes through the side of the trickle filter box.
Inside the trickle filter box is a float switch, much like the float switch
that is used in the basin of your toilet bowl. It is not electric. The two
primary differences are that: it is much smaller, and it is made entirely out
of plastic - there are no metal parts.
When water evaporates from the
tank it in turn affects the water level in the entire system, including the
sump in the trickle filter. Therefore, when the water level in the sump in the
trickle filter drops, the float switch in turn drops, which then opens up a
small valve connected to the switch. When the valve opens up, water from the
blue storage bin is allowed to pass through in a drop by drop fashion, thereby
topping up any evaporation.
I fill the storage bin up
weekly. There tends to be greater evaporation in the winter time owing to drier
air, as well as increased air circulation form the furnace. If a float switch
and external top-up sump is not used, then you will have to be diligent with
respect to watching for evaporation, as once the water level gets too low, the
pump will start to suck air. This will not be a problem for a few hours or even
an entire day. However, should you go away for a few days, your pump could
easily be irreparably damaged through over heating.
- This shot is a
frontal view of the previous picture. As it can be seen, the main filtration is
a under the tank trickle filter. It is filled with plastic flex rings. The pump
that is used is a Little Giant 4MDQX SC, which circulates roughly 1200 GPH. The
drain from the pre-filter can also be seen, showing a stiff 1.5" PVC pipe
connecting the bottom of the pre-filter to the top of the trickle filter. There
is also a 1" bi-union ball valve connecting the pump to the trickle filter. The
bi-union feature comes in handy when the pump needs to be removed for cleaning,
or when the trickle needs to be removed. Also, is a 1" single union ball valve
from the exhaust of the pump. This allows the user to reduce the water flow
into the tank for any necessary reason, such as cleaning, feeding etc.
The lighting is composed of one
175 watt, 5500 Kelvin metal halide lamp, and four, four foot 40 watt Zoo Med
Reptisun 5.0 florescent lamps. All lights are on timers following the photo
period of the day and the seasons.
- This picture
represents a transition in trickle filter design and terrapin housing. After
having used a 180 gallon glass tank for a few years, and watching the terrapins
swim endlessly up and down the sides, I felt that perhaps a round tank would be
better for their state of mind. I thought that maybe the roundness would create
the illusion of an endless swimming space. Underneath the basking platform, is
a internal prefilter. This prefilter is held in place with a plastic tank
adapter that has been screwed into the bottom of the kiddy wading pool. To aid
in forming a better water proof seal, I added quite a bit of silicone as the
bottom of the pool was not perfectly flat. The trickle filter design was
basically the same as the one pictured under the 180 gallon tank picture.
The three primary differences were:
- The 180 gallon tank has a hang on prefilter whereas the
kiddy pool is drilled with an internal prefilter;
- The trickle filter on the 180 gallon tank is a custom made
acrylic unit filled with flex rings whereas the trickle filter on the kiddy
pool was made out of two Rubbermaid containers (similar to the earlier picture,
only much larger) and:
- The pump on the 180 gallon tank is an external Little Giant
4MDQX SC, which circulates roughly 1200 GPH whereas the pump on the kiddy pool
was a Quiet One, which circulates roughly 750 GPH.
The cost of the 180 glass tank,
metal stand, trickle filter, hang-on prefilter, bio-media, pump and all of the
fittings and piping was roughly $1200. The cost of the kiddy pool, home made
wood stand, Rubbermaid storage bins, fittings, piping, internal prefilter, lava
rock and Quiet One pump was roughly $350. The choice should be fairly obvious.
- This picture
represents an above the tank trickle filter. As it can be seen, the trickle
filter is an aquarium that has been converted into a trickle tower by
siliconing another glass plate over the open side of the aquarium, and by
removing one of the end plates which serves as the top. There is a (roughly)
two inch space left at the bottom which allows the water to pass back into the
tank. I have also added a piece of glass on either side of the opening so as to
create a smaller opening that the water is channeled through.
The bio media is standard
plastic flex rings, which are resting on top of plastic egg crate, which is in
turn secured inside the tower at the same height as the opening. On top of the
flex rings is a piece of sponge and a drip plate, and then on top of that is
some floss that can be easily discarded.
One end of the aquarium has
been removed, and has been replaced with a 3/8" thick glass plate that has a
hole in the centre. In the hole, is a plastic tank adapter that is connected to
the 5/8" flexible tubing from the pump. The 3/8" glass plate is the lid to the
As it can be seen, the pump is
supported outside the tank on a small shelf. The intake is simply constructed
out of some PVC elbows and some flexible tubing. In this application, the pump
is an Eheim 1060, which circulates roughly 540 GHP. For a 90 gallon tank, this
is adequate. Personally, I prefer the Ehiem pumps because they are incredibly
quiet, the parts are easily replaceable, and the shaft is ceramic, making it
almost indestructible, it certainly offers very low resistance and is tolerant
to salt water.
For circulation, I have also
added a small submersible Fluval 4 filter. In this tank, I had four ornate
adult (2:2) diamond back terrapins.
- This picture
represents the cheapest, and easily constructed trickle filter. It is made out
of two Rubbermaid containers. The round one is filled with crushed coral to
serve as the bio-media. The bottom of the round container is drilled with
numerous small holes to allow the water to pass through. In the lid, is a 1/2"
fluval elbow which holds the tubing from the pump.
As the picture demonstrates,
the return to the tank is simply a 3/4" threaded PVC elbow, with a barb that
has been screwed into a hole cut in the centre of one of the ends of the
rectangular Rubbermaid (the sump). Attached to the barb are a couple of
Aquaclear 500 intake stems (coincidentally enough, they fit perfectly). They
were attached to reduce the amount of splashing occurring in the tank with the
water dropping almost one foot. Flexible tubing that fits over the barb would
This filter is ideal in
emergency situations. For the set up depicted here, I had acquired a large
adult female diamond back terrapin from a Chinese fish market. Not having
anywhere to put the terrapin on a more permanent basis, I threw this filter
together from parts that were lying around the house. The tank is a shallow 40
gallon, measuring 36"X18"X15". The pump that was used here is the second
smallest Rio submersible, perfect for small application such as this one.
Any questions concerning the design and application of these
filtration setups should be directed to:
- Jared Purdy firstname.lastname@example.org
- 384 O'Connor Drive
- Toronto, Ontario
- M4J 2W1
- (416) 424-1676
- (If you would like to speak to Jared, please do not
call between the hours of 10 p.m. E.S.T. and 8 a.m. E.S.T.
This article was published on the internet 1997, and is the
copyright © of Tricia Power and Jared Purdy. This page will be updated
periodically. All rights reserved. No part of this page may be reproduced in
any form without the permission of the author or the photographer. Please
contact Jared Purdy or Tricia Power at the above email address if you would
like to use this article for educational purposes. :)
Mar, 19, 2010
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