how to reduce flow from MaxiJet 1200

So, I used to have it hooked up as the return pump, but went ahead and threw my stock pump back in and hooked up the powerhead attachment for the MJ1200. The problem is that it's too aggressive and even pointed at the top of the water across the corner of the tank... it's just got too much flow. Within a minute, the sand starts to pick up. The corals seem to like the increased flow (they all have inflated more with me triggering it on for a minute or two and then letting the water clear, then giving it another go for a couple cycles). My question is, how can I decrease the flow to the point that it doesn't stir up the sand like crazy? This is in my Biocube 29.

I thought about trimming the blades which should decrease flow but might destabilize the propeller. I'm open to other ideas.

 

Its not the amount of flow, its the velocity through the small jet type nozzle.
Thats why most people use powerheads like the Koralias, Evolutions, Tunzes, Seios, Sicce Voyagers and similar. The flow is more dispersed so does not kick up sand.

One thing I have seen people do with MJ powerheads is cut the nozzle completely off and widen the outlet slightly so it spreads the flow out. Other options are the MJ modifications you cna buy that turns them in to a prop pump like the Koralias but I tried both major brand kits and both vibrated, still used scution cup mounts unless you want to spend a fortune on magnets and did not work as well as my Koralias or Evolutions.

I have a Koralia K1 and a Koralia Evolutions Nano425 in my 16G bowfront and could use a little more flow and both of those put out much more than a MJ1200 at 1/3 to 1/4 the wattage. I also have 3" of southdown sugar sand in the 16G and it stays put.

 

This is the type of "outlet" it has on it... it's more of a shroud.

 

Where do you have it mounted on your tank?

 

The head itself is about 1/3 down from the top and it's pointed up (not directly up). It points towards the other corner at the surface so up at around a 10-15* angle. Shooting from the front left corner to the rear back corner.

 

bump

 

Are you refering to the maxijet pro?(see pic) I bought 2 of these for my 55 and cannot run them as a (koralia) type pump,i had to put them back together as standard powerheads as they were a beast in my tank,sloshing water over the rim at top,sucking air from above creating a vortex whirlpool action no matter how low i moved them.When i would move them low enough to not suck air,it was a total sandstorm.After many,many hours of messing with them,i ended up just switching them back over to regular (old style) powerheads.In circulation mode (when set up as a korolia type) they push 1300gph with the propellar,in old school powerhead mode the push 295gph i believe with the included impellar.Trimming the blades won't work as they are balanced like an airplane propellar and you would have MAJOR vibration and noise.I wish I had bough 2 of the 600's instead of the 1200's thinking they would be like koralias,but these pumps are much,much stronger.HTH


first pic-new style,2nd is old style

 

Yes, I have the "pro" version that creates the wake of an outboard Evanrude. I can see about modifying it to be the "old fashion" version. I was blown away when I tested it it in the 10 gallon tank... thought it might be better with a more dense medium and larger water, but yes I get random large air bubbles trapped in the flow

 

Haha,i tested mine in a 5 gallon bucket when i first got them.Don't do that.I got wet.And yeah,I had a Johnson 9.9 with less output than these maxijets.

None the less,way way too much for a nanocube in "pro" mode.

 

Thanks! Switching it worked great. It's a bit unsightly, but it'll give me a chance to see if I like the increased flow and how the inhabitants like it.