Maxi-Jet "stream" mod

[Anonymous]

Yeah, if you have small fish it could cause trouble if it changed direction when you weren't home. Though I don't think I need to worry about the fish I have in the tank now, I still plan on installing an arcylic rod on that mj soon, maybe tonight.

And it is easy!
I'll post pics tonight.

 

[Anonymous]

Ok, here are some shots of my MJ mod with the steel shaft and rigid airline tubing.

The first one is a shot of the entire mod on the pump, the second one is a top-down shot of the mod without the end cap on, and the last one is a picture of the shaft and prop assembly.

There is really not much to it.

-Marcus

 

[Anonymous]

Marcus,

It looks like you didn't glue the bottom cap back on the magnet. So you just put the black and red cap on the bottom of the steel shaft, right?

How does that work?

I saw on MJmods.com that you can just extend the rigid airline through the magnet to hold it in place. Did you ever try it that way?

I purposefully cut my airline longer so that I can experiment around a bit before glueing it in place.

Louey

 

[Anonymous]

The rigid airline tube goes all the way through that magnet. I broke off both ends of the original impeller and pulled out all the plastic so that the magnet was totally hollow.
When I first built this prop assembly I had the rigid airline tube running all the way through the magnet and sticking about about 1/8" out the back. But it made some noise that way, so I tweaked it some and cut the rigid airline tube shorter, so that it goes most of the way through the magnet, but not out the other side. That seemed to make it much quieter (but I don't know if that was it, or if it just went together better when I rebuilt it the second time... in any event, I built my next two mods the same way, with the tube stopping inside the magnet, and I haven't had any problems with noise like other people have reported).

That black and red cap is just stuck on the end of the steel shaft (and it doesn't fit real well). I don't know if it is actually necessary or not. I thought it might act as a damper to keep the vibration down, but it might just be decorative.

-Marcus

 

[Anonymous]

These maxijet mods are fun!

We put one in the 65, in the upper back corner, pointed along the length of the tank (three foot long tank). It sure is a lot of flow! 8O

FWIW, it hasn't wrecked the sand bed, but it is gradually moving some of the sand around over time.

The one we put in the 65 seems to be a bit louder than the ones Marcus put in his 120, and I wonder if the orientation of the thing might make a difference. I glued the maxijet arm to the end of mine so I could hang it on my tank and have it blow across the length of the tank, while Marcus put his pointed down to make more of a churning flow.

I think the little bit of back pressure they get when pointed down might let them run quieter, as I have also noticed that when I put my hand in the stream it quiets down significantly. This weekend sometime I am going to try and hang mine pointed down and see what it does to the noise. Right now it is just noisy enough that it makes me want to tinker with it, but it isn't soo bad I would take it out.

 

[bleedingthought]

FWIW, it hasn't wrecked the sand bed, but it is gradually moving some of the sand around over time.

Yeah, this is the only problem I foresee. The right side of my tank has a lot of corals on the sandbed itself, so I need to avoid having them be buried. Still trying to figure out a way in my head...

 

[Anonymous]

I have just been keeping an eye on things and moving corals around to accomodate the new sand formations. I rather like how the top of the sand moves around a bit on that side of the tank from the flow though. It stays nice and white!

 

[bleedingthought]

But the problems I've had with sand seem to including the flow moving the sand from one place to the point where you can see the bottom of the tank! And obviously, it creates a huge "wall" of sand around the burrow.

Post pictures of your tank, if you can. I'd really like to get an idea of how you're positioning things, laura!

Thanks in advance!

 

[Anonymous]

The problem I see with these is the direction the prop chooses to spin. I have used the acrylic rod "stopper" and it doesn't work worth a crap. I have used shrouds with and without the stopper and it doesn't appear to change the direction one bit. There doesn't appear to be any rhyme or reason as to which direction the prop spins. I plug it in and out and sometimes it changes direction and sometime it doesn't.

Louey

 

[bleedingthought]

The problem I see with these is the direction the prop chooses to spin. I have used the acrylic rod "stopper" and it doesn't work worth a crap. I have used shrouds with and without the stopper and it doesn't appear to change the direction one bit. There doesn't appear to be any rhyme or reason as to which direction the prop spins. I plug it in and out and sometimes it changes direction and sometime it doesn't.

Louey

With the maxijets, there's no rhyme or reason as to which direction they will start spinning. It's luck of the draw. The stopper is supposed to stop the prop when it is spinning the wrong direction and then the maxijets will therefore spin the opposite direction which would fix it.

Have you tried skimming through the RC threads?

http://reefcentral.com/forums/showthrea ... =DIY+tunze

http://reefcentral.com/forums/showthrea ... genumber=1

The second link should be more compact or "tried and true." I've read many of the pages and it's kind of like wetwebmedia, in the sense that people have had problems with their mods and others have helped through their problems. You should be able to find something there.

 

[Anonymous]

Thanks for the links, bleedingthought.

I have not read much of those threads because they are so long.

I'll take your word for it and read up on the second link.

I guess what I need more than anything is to know how to troubleshoot the stopper to make the MJ change to the correct direction.

Louey

 

[bleedingthought]

And this is from ReefChili:

What is the stopper and how do I use it ?

Because the maxi jet runs on alternating current (AC) power it can spin both left or right and will do so randomly
when you first plug it in. if it starts going the right way then perfect but half the time it will start going the wrong
way and end up sucking water in the front and blowing it out the fins on the side. This is where the stopper
comes in. the stopper is simply a piece of acrylic rod shoved through the side of the housing. I drill a 3/16” hole
about a 1/8” below the top of the housing (just under the cap) and glue a ½”-1" piece of 3/16” acrylic rod. What
happens when the pump starts the wrong way is it pushes the whole impeller up towards the cap when this
happens the prop will slam into the stopper (acrylic bar) and bounce back the other way and start running in the
right direction. This is extremely easy to implement and works very well. Some people have found with the
octura props that you don’t need a stopper because the ends of the prop extend up and actually slam into the
centering cap itself. I personally always use the stopper bar because it works so well , costs almost nothing and
takes about 20 seconds to install . Mother always said “if it an’t broke don’t fix it” : )

Not sure if you used their directions to build the mod or not, but here's the link to their page:
http://www.reefchili.com/MJmods.html

How long is your stopper? From the sounds of it, you might either have it too short or too close to the end of the housing.

HTH.

 

[Anonymous]

My stopper is 3/4" long and the hole was drilled 1/8" from the end of the shroud, just below the cap.

I do think it should be farther in.

I think I'll try one further down inside the shroud.

Louey

 

[Anonymous]

I'd try it further in.
The 1/8th of an inch thing is unworkable IMO, the prop will still hit the endcap at the same time it hits the stopper.

My stoppers are more like 1/4 to 1/2 of an inch from the endcap.

 

[Anonymous]

Moving the stoppers back seems to work now.

I now have a functional unit that is almost ready to go in the tank.

Tonight I glued the MJ to a large magfloat using Weldon 40. I plan to use this MJ on the magfloat to storm the crap out of my tank. I'll also use it for supplemental flow facing the the base rock when it is not being used for strorming. If it is not too noisy, it will be a welcome addition to my tank. If this one holds up and doesn't make too much noise, I may make others to add even more flow.

Louey

 

[Anonymous]

Here's a couple of pics of the flow with the MJ running in my mop sink.

The flow is impressive to say the least.

Louey

 

[Anonymous]

After running mine for a few days, I have decided it is too noisy to use continuously. I will only use it to storm the tank on ocassion. With it mounted on the magfloat, it will work very well for that.

I will also use it to mix new saltwater in my 130G water storage vessel. It will do that very well.

I did like the added flow in my tank. Now I really want another Tunze or a Vortech.

Louey

 

[bleedingthought]

Try using other props or different rods to see if the noise will damper. Unless you don't want to mess with it more.

 

[Anonymous]

I may mess with it a little more in my spare time.

Louey

 

[bleedingthought]

I was supposed to have gotten the kit by now but haven't been able to. I've been thinking though:

With the amount of LPS in my tank, the 2"-3" of sand, I'm starting to wonder if I should buy some MJ900s and mod them or just get a smaller prop for the 1200s I already have. I'm hoping to only have 1 or two of these in my tank. Any suggestions? :?