To much back pressure on mj600

[Ryan winder]

recently bought a cobalt mj600 and a tlf 150 reactor. Whenever I dial down the flow rate to make the gfo lightly tumble it puts a ton of back pressure on the mj600 and causes it to rattle pretty loudly. Is this the nature of the beast or can I relieve pressure and quiet down the pump somehow?

 

[ndrwater]

MJ's aren't the quietest pumps out there, but a rattle is not normal. Is the bottom part of the pump seated properly? If the impeller is rattling around, something is definitely up

 

[Ryan winder]

It only rattles when I use the ball valve to dial down the flow rate. If I open it up completely it’s totally silent but then I have a gfo tornado in my reactor

 

[ndrwater]

You could potentially use a "tee" and another ball valve, but a 600 shouldn't be excessive flow IMO.

 

[Ryan winder]

160 gph through a gfo reactor isn’t to much

 

[ndrwater]

Not at all...

 

[Ryan winder]

Maybe I’m just being ignorant but I thought a slight rumbling on the top surface of the gfo was sufficient movement. If I open it up and get 160 gph it’s a total whirlwind of gfo media inside the reactor. That’s not to much?

 

[Ryan winder]

I wonder if it’s because I’m using such a small amount of gfo that’s why it’s tumbling so vigorously with such a little amount of flow. I’m using 30 grams and it’s about an inch up the reactor chamber. The Tlf user guide says a minimum of 2 inches. Should I try doubling up on the gfo? Will that do any harm to my tank