Maxi-Jet Modifications: What’s all the fuss? It is without a doubt that the Maxi-Jet line of Powerheads by Aquarium Systems is a workhorse of the marine aquarium hobbyist. These pumps are used for everything from aeration, water movement, filling and draining to even mixing saltwater for water changes. Maxi-Jets have gained a reputation in the hobby for their durability. There are not very many powerheads that can take the abuse we put them through, but these do. I also do not believe that any other pump has had more discussions on modifications. Especially considering all the talk is coming from the hobbyist side of the aquarium. Since the number one use of the Maxi-Jet is for adding water movement in our aquariums, we should discuss the abilities of these little powerhouses. The chart below shows how the current models of the Max-Jet line stack up.
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Model
|
GPH
|
Watts
|
Price
|
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Maxi Jet 400
|
106
|
5
|
$14.99
|
|
Maxi Jet 600
|
160
|
7.5
|
$15.99
|
|
Maxi Jet 900
|
230
|
8.5
|
$19.99
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|
Maxi Jet 1200
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295
|
20
|
$22.99
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As you can see the model 1200 is the largest powerhead in the Maxi-Jet line and is perhaps the most used. For such a small package the MJ-1200 is capable of pushing 295 GPH at 0' head and only uses 20 Watts of power. For the budget conscious, this is a definite advantage. And because the series is so well constructed, and long-lasting units, they are highly recommended for wavemaker use. On the web, there are numerous forums with postings of how to modify a Maxi-Jet. One of the largest is the "Hitchhiker's Guide" to the Maxi-Stream Mod thread on Reef Central. Currently this thread has split three times and is over 120 pages long. The basic idea is to increase the area used for intake, this allows for more water in. At the same time you put in a larger impeller, or in the case of most mods, a propeller, to increase the ability to push the water. One of the early modifications was the “hacksaw” method. It is a simple mod that produces some interesting results. The unchanged Maxi-Jet produces a stream of water. It is limited by the input as to how much water can be sucked into the pump. Likewise the output nozzle restricts the amount of water being pushed out.
Figure 1. Before and after pictures of the Maxi-Jet "hacksaw modfication. Photos courtesy of Scott Rowe
In the “hacksaw” method you simply cut the nozzle off. This allows for a wider stream, but does not increase the amount of flow. To increase flow, more water has to be drawn in. To do this you need to drill holes in the powerhead’s coverplate surrounding the input. This allows the device to draw in more water, therefore increasing flow (See Figure 1). The conservative estimate is that this modification creates an increase in the range of 400 to 500GPH. One of the interesting caveats to this modification is flow direction. When used on a wavemaker, or other timing device, the flow direction will change with each start/stop of the powerhead. On the Maxi-Jets each time they turn on the direction of the impellor changes. Normally this is not seen since the water is forced through the nozzle. However when you cut the nozzle off, the direction of the flow is determined more by which direction the impellor is spinning. The water will either come out on the left or right side of the rectangular opening. This makes some interesting random water movement in the aquarium. There you have it, an inexpensive way to improve water movement in your aquarium. This simple modification can help improve the overall health of your aquarium. By helping corals remove waste, eliminate dead spots, keeping nutrients in the water column, the overall health of your tank will be improved. Now this is not the only modification that can be done to the Maxi-Jet and in the next article we will discuss other improvements. Some of these modifications increase the flow upwards of 2000GPH and have it competing with the big boys. |