Easy MJ Mod

[rfequity]

I tried this today on my MJ900 in the sump of my AP24. I left the output the same so it could plug into tubing run up to Loc Line. I sawed off the input and drilled holes around it. It didn't change a thing.

[blooper74]

I did this on a MJ1200 I had in my reef box, I gotta say it works pretty good. I put the MJ in a tank of water and sand and got the usual, then I did the mod and the sand went everywhere. I had the MJ is the same spot and pointed in the same direction for both tests. I am glad I found this little mod, it is a gem of a find.

[ls7corvete]

I tried this today on my MJ900 in the sump of my AP24. I left the output the same so it could plug into tubing run up to Loc Line. I sawed off the input and drilled holes around it. It didn't change a thing.

Yea I think this mod just trades pressure for volume. You get alot of volume at much less pressure, no good for pushing through locline or similar.

[mahi mahi boy]

Was there testing done? Did someone drain a volume of water w/ & w/out the holes to see if the holes made a difference?

[rage1148]

Hey Travis,

 

Just wanted to know if the blue background was painted on?

[RP Beesh]

cool idea.

[Travis]

Hey Travis,

 

Just wanted to know if the blue background was painted on?

 

Nope

[Drez]

Was there testing done? Did someone drain a volume of water w/ & w/out the holes to see if the holes made a difference?

 

Given the mod, that's not too easy to do b/c you can't hook a hose up to the output anymore as its been sawed off. Even if you could hook up a hose, the hose would reduce the output and so youd only see the improvment as a ratio and it would be biased in favour of the unmodded MJ as hooking up a hose would negate part of the mod itself (e.g. diffusing and widening the output vs. restricting it with a hose).

 

If someone can figure out a pre/post test though would be nice to know aprox how much improvment is seen. Maybe holding the pump in hand?

 

I'll be doing this ASAP. Just waiting on a Dremel to do the sawing.

[barmer]

Now the only drawback to this mod is that everytime the pump is turned of, then turned back on, the flow goes to a different place. But that also could be viewed as a good thing because then it would make for a TRUE random wavemaker.

 

I plan on doing this mod on my two MJ600's. I then plan on attaching these to a relay timer that I've got and setting them up to stay on for a few minutes and the switching off for a few seconds. My hope is to have them alternate their current randomly when they switch back on. My questions are thus:

 

1. Has everyone seen the direction of flow change when turning off and on or has it been hit and miss depending on how far you cut the nozzle back?

 

2. How long should I set the timer for "ON" before having it shut off and then restarting for a good wave effect?

 

3.How long of a pause before restarting each time?

 

4.Will modding 2 MJ600's be too much or too little for a 20gal High?

 

Thanks....

[Travis]

1. Has everyone seen the direction of flow change when turning off and on or has it been hit and miss depending on how far you cut the nozzle back?

 

2. How long should I set the timer for "ON" before having it shut off and then restarting for a good wave effect?

 

3.How long of a pause before restarting each time?

 

4.Will modding 2 MJ600's be too much or too little for a 20gal High?

 

1. With the way mine are cut, I get a dirrection change everytime I turn them off then back on.

 

2. I would say about 15-30 seconds

 

3. To make sure you get a dirrection change, plug the pump up, then watch to see how long it takes the propellor to stop, should only take a few seconds.

 

4. No way, I am running the two modded 1200s on my 20 High and I find it to be the perfect flow for my SPS, although I am considering going back to BB because it is seriously kicking up some sand!

[tinyreef]

just did it on a mj900. i replaced a mj1200 i had in position just for a (purposedly skewed) comparison sake.

 

so far, it looks the same in resulting flow dynamics (i would even say it's a bit stronger but it's probably more because of a wider spread in the wave/flow too).

 

but again, it is a downsize to a 900 compared to a 1200. i'll be looking at the 900 for a few days and then maybe swap upwards to a 1200 if i think it's insufficient (which i don't at this early stage).

[barmer]

2. I would say about 15-30 seconds

I didn't think it would be suck a short interval. I thought it would be more like 2-3 minutes of run time in between stops. Is there an advantage of having them switch this rapidly? I know the switching on and off will shorten the lifespan of the MJet but will it be a significant amount?

[Travis]

I suggested a shot intervale because I used an Sqid SCWD in the past and the interval was about 7 seconds.

[barmer]

Seems like it might be stressful to your fish if you have any. But then again we are talking about a native enviroment from which they live that is in constant motion. Hhhhhhhmmmmmmmmm......................

[mahi mahi boy]

Given the mod, that's not too easy to do b/c you can't hook a hose up to the output anymore as its been sawed off. Even if you could hook up a hose, the hose would reduce the output and so youd only see the improvment as a ratio and it would be biased in favour of the unmodded MJ as hooking up a hose would negate part of the mod itself (e.g. diffusing and widening the output vs. restricting it with a hose).

 

If someone can figure out a pre/post test though would be nice to know aprox how much improvment is seen. Maybe holding the pump in hand?

 

I'll be doing this ASAP. Just waiting on a Dremel to do the sawing.

You could do it in a pitcher w/ a hose hooked up to the positive end of the MJ. You don't have to drain all of the water out to determine any difference. Just the amount of water pumped out and the timings, w/ equal water portions as well. I'll be waiting on your test.

[Drez]

You could do it in a pitcher w/ a hose hooked up to the positive end of the MJ. You don't have to drain all of the water out to determine any difference. Just the amount of water pumped out and the timings, w/ equal water portions as well. I'll be waiting on your test.

 

You cant hook a hose up to the positive end, look in the picture, its cut, its too wide for a connection. Even if you could, the test would not be valid unless the hose was the same diameter as the modified output. By bottle-necking the output, you negate the modification of opening the ouput to be wider. A bottle-neck will increase pressure and reduce output (gph).

 

You could test only moding the intake but thats only half the mod and most likely not nearly as effective as the mod as intended.

[mahi mahi boy]

You cant hook a hose up to the positive end, look in the picture, its cut, its too wide for a connection. Even if you could, the test would not be valid unless the hose was the same diameter as the modified output. By bottle-necking the output, you negate the modification of opening the ouput to be wider. A bottle-neck will increase pressure and reduce output (gph).

 

You could test only moding the intake but thats only half the mod and most likely not nearly as effective as the mod as intended.

Of course you can't do it to the modded MJ positive nozzle, that's the whole point of the test! Of course it's valid. LOL It will tell you if the drilled holes make any difference. And the factory nozzel will not negate the results in that test from the second half of mod, it's not that restrictive. Until the testing, I see the intake mod results as anecdotal. IMHO

[Drez]

Of course you can't do it to the modded MJ positive nozzle, that's the whole point of the test! Of course it's valid. LOL It will tell you if the drilled holes make any difference. And the factory nozzel will not negate the results in that test from the second half of mod, it's not that restrictive. Until the testing, I see the intake mod results as anecdotal. IMHO

 

The point of the test is that you can’t test the modded MJ output nozzle? I hardly see how that makes sense. If you can't test it properly don't bother testing it at all.

 

Yes the results are anecdotal, but doing poor tests in a systematic fashion is worst then not having any testing at all. It’s misleading. Testing the modified input but stock input is a poor reflection of the modification, period. Flow is equal to pressure divided by resistance. If you leave the pressure (the pump) as it is and do not alter the resistance (the bottleneck in the output nozzle) then you can’t expect much improvement in flow.

 

Think of it like your tap. Consider the sink the MJ housing, the faucet the input and the drain the output. If you crank up the input (turn the taps on more), you’ll improve the flow out the drain up until you reach the maximum output the drain can handle given the pressure pushing the water out the drain (gravity). You could improve the flow only marginally by increasing the input at this point. The only other ways to increase the flow is to expand the drain (cut the output) or to apply greater pressure (would be akin to altering the pump itself.)

 

Thus, testing the modified input without altering the output is a moot point. I'd rather have the anecdotal hear say of my fellow reefers.

 

My 2c.

[mahi mahi boy]

We're on the wrong page here. What I'm saying is anecdotal is that the new holes increase or decrease GPH. Now I guess what you're saying is that all testing is irrelevant unless you modify everything and do the mod as a hole.? Which I don't understand because I'm not addressing the flow mod. And I don't think the factory output nozzle would cause enough turbulent or laminar flow to even effect the GHP considerably. So I wanted to compare the two w/ just hole mods to see if there's any difference. I'm just curious as to what gain the extra holes have, that's all.

[Drez]

We're on the wrong page here. What I'm saying is anecdotal is that the new holes increase or decrease GPH. Now I guess what you're saying is that all testing is irrelevant unless you modify everything and do the mod as a hole.? Which I don't understand because I'm not addressing the flow mod. And I don't think the factory output nozzle would cause enough turbulent or laminar flow to even effect the GHP considerably. So I wanted to compare the two w/ just hole mods to see if there's any difference. I'm just curious as to what gain the extra holes have, that's all.

 

O'K. I think we were a little off here.

 

So you want to see if drilling holes into the intake alone will increase flow. I guess if you wanted to use it as a pump rather then powerhead or you wanted to keep a more direct flow vs a more diffuse flow casued by cutting the output then this could be valuble.

 

Basically what I was getting at was that I'm fairly certian that the whole will be greater then the sum of its parts. That is, flow increase due to modding intake alone+ flow increase due to modding output nozzle alone will not = flow increase due to moddification of both at once.

[Travis]

whole will be greater then the sum of its parts.

Quoting Aristotile there? lol

[Drez]

Quoting Aristotile there? lol

 

Yea I can't coin that as my own, Need to have a footnotes option

[Socalsuperhero]

O'K. I think we were a little off here.

 

So you want to see if drilling holes into the intake alone will increase flow. I guess if you wanted to use it as a pump rather then powerhead or you wanted to keep a more direct flow vs a more diffuse flow casued by cutting the output then this could be valuble.

 

Basically what I was getting at was that I'm fairly certian that the whole will be greater then the sum of its parts. That is, flow increase due to modding intake alone+ flow increase due to modding output nozzle alone will not = flow increase due to moddification of both at once.

 

I think that the confusion here lies in the fact that the main goal of modding the maxijets is to change the functionality of the device. Maxijets are designed as pumps. However, when used in a tank the only purpose is to push water around. The problem is that the maxijets function very well as pumps, but are ### poor at just pushing water around. This is because the two functions are in and of themselves completely different. Perfect example of this is the stream mods that are available for mj's. Is the motor working harder? No. The entire system is more efficient at moving volumes of water because that's what it's designed to do. Could you use it to pump water through plumbing, maybe, but it wouldn't be nearly as effective as the original mj was as a powerhead.

 

Now, back to the subject at hand. The whole purpose of this ghetto mj mod is to remove some of the features of the pump design that prevent it from being more efficient at simply pushing water around in a tank. This should not be though of as something to make a mj functioning as a pump better, stronger, or faster. If that's what you are looking for then plug it into 220vac or something, just don't blame me when your house burns down.

[ls7corvete]

I think that the confusion here lies in the fact that the main goal of modding the maxijets is to change the functionality of the device. Maxijets are designed as pumps. However, when used in a tank the only purpose is to push water around. The problem is that the maxijets function very well as pumps, but are ### poor at just pushing water around. This is because the two functions are in and of themselves completely different. Perfect example of this is the stream mods that are available for mj's. Is the motor working harder? No. The entire system is more efficient at moving volumes of water because that's what it's designed to do. Could you use it to pump water through plumbing, maybe, but it wouldn't be nearly as effective as the original mj was as a powerhead.

 

Now, back to the subject at hand. The whole purpose of this ghetto mj mod is to remove some of the features of the pump design that prevent it from being more efficient at simply pushing water around in a tank. This should not be though of as something to make a mj functioning as a pump better, stronger, or faster. If that's what you are looking for then plug it into 220vac or something, just don't blame me when your house burns down.

 

 

Actually probably better to increase the frequency of the pump from the 60hz that its getting, Its the frequency that determines the speed.

 

Like I said you guys are trading head for volume, lol. Head is good for going through resistance, volume is good for moving coral polyps.

 

Anyways you all got it wrong. The best way to test these would be to run them both in a circular or doughnut shaped tank and measure the speed of the water that is acheived with both pumps...duh. LOL.

[latazyo]

does this provide wider flow like a seio/tunze?