Bubble magus t11-t12 noise!!!

[larryhaynes]

Hey all, does anyone out there have any experience with these dosing pumps? I know that this model is relatively new, and I have never used dosing pumps before!! Question is I set up my master unit about a month ago for a B and C they seemed a little loud then but I wasn't too worried about it because they were doing their job last night I set up my 4 pump slave unit and they are even louder pump number seven is extremely loud and grindy sounding it doesn't sound right so question is does anyone have any experience with these pumps and should I be concerned with my slave I am dosing red sea coral color ABCD So I'm not extremely concerned at the moment but should I be any advice from experienced users will be appreciated

 

[larryhaynes]

Here is the setup

 

[larryhaynes]

My mistake the one making the most noise is pump number six it is probably 3 to 4 times as loud as the rest