I was just busy modding my Kangaroo 224 Pump this weekend to make it "Reef-ready", and decided that there may be interest in these mods since I had a tough time trying to find them myself. The Kangaroo Feeding pumps are another alternative to Reef dosing pumps for a handy DIYer. Given that if you watch ebay for them, a DIYer can net a good litle doser for a fraction of the cost that a new reef one will run you. Granted they run in the 100's of dollars for new kangaroos, but I often see used 2nd hand pumps for under 35-50 bucks. I paid $15 for mine so they are out there if you look. Thanks to SNTLewis on Reefcentral.com who provided me with the pics for the 324 mods, and I've done them on my 224 as well to verify it works on the 224 models.
You want to make sure that the doser can fufill your evaporation needs, but for my needs it should be fine. The Kangaroos can do a max of 300ml/hr which works out to 1.9gal/day with standard tubing. I've read that some reefers increase the tubing diameter to effectively increase the max dosing cap for the pumps. Silicone, "Pharmed" or Tygon tubing is in use by various reefers from my investigations. One good supplier is
www.usplastic.com where I got 20ft Tygon tubing 5/32" ID x 7/32" OD x 1/32" Wall for $0.32/foot for $11.50 total shipped. Far cheaper than pump sets and will last much longer. The other materials are longer lasting, but higher priced. I'll use this for now and experiment in the future to determine the "best" stuff.
There's two simple mods you can make to remove the limitation of needing to buy the pump sets @ $3-15 each. If you can wield a screwdriver & a soldering iron, you can make these mods. It took me 20 mins and the first 15 minutes was dedicated to practicing my novice soldering skills on a junk PCB board so I didn't screw up my unit with a solder joint gone bad.
The Kangaroo 324 & 224 are very similar on the inside for what we will be dealing with.
For reference all descriptions will be given with the bottom of the pump nearest you and the top away, with the front panel down on the table. The motor is toward the bottom, the handle would then be top and the power cord socket would be on the right side.
First make sure the unit is not plugged in and turn the it on its front so you have access to the back. Next, crack open the case removing 4 screws - two on the bottom and two just under the handle, which you'll have to flip up to access them. Gently lift up the back and you sould see the guts of the pump. If you like, you can disconnect the battery connector so that you have more freedom while you work. The other thing that helps is to remove the screw which holds the grounding wire to the metal sheild over the auxillary battery pack. Just make sure to put them back when you are finished with the mods (as an ungrounded device could lead to big probems if you do not replace the wire.) At this point the back should be free and you can set it aside while you work.
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No Set Error bypass: This mod allows you to use any tubing you like instead og the special pump sets made by for the unit.
This mod connects a terminal prong to a solder joint on the board. Find two points: one is a 6 prong terminal socket connector in the bottom left part of the board very near the motor noted on the board with "TP2". You will be concerned with the 2nd terminal from the bottom (2nd from the motor).
For the second location, look for the "E2" note on the board with 3 solder joints aligned horizontally. It's only 2 or 3 inches from the terminal sockets. You want the middle solder joint.
Cut yourself a wire and carefully solder it to the board and make sure you don't melt into the neighboring solder joints to create a short circuit. Then solder to your prong and that's all.
No Flow Error Bypass: Disables the flow sensor that makes the unit think no flow is going through the tubing. There really is, so we don't want this warning.
This mod connects two prongs on the Logic Chip embeded in the board. On the bottom row of prongs count the 6th prong from the right, and mark the chip with a pencil. Then mark the 12th Prong from the right with another pencil mark. You don't have to remove the chip to do this mod.
I found it easier to take a longer piece of wire, and strip off about 1/2" of the insulation. I then hooked the wire around the target prong and used a pin or something to work with it. After you've looped it around the prong, wrap the wire around itself to form a tight "twist-tie" style joint around the prong. This secures the wire to the prong and GREATLY helped me solder. Without doing so, holding the wire, solder, and soldering iron all together to get them heated evenly was nearly impossible. Careful not to heat much more than you need to, as you can (and I did a bit) melt the plastic terminal that the chip plugs into. Worse would be melting or screwing up the chip itself, which if you are carefull, you souldn't do.
That's all there is! You now have a reef-ready doser that you can use regular silicone tubing to operate. I don't take any credit for coming up with these mods, I just wanted to share them with others since I had a tough time coming accross them. On a budget, Kangaroo pumps make a nice alternative to a conventional doser if they will fit your needs.
Hope this helps anyone out there!
