Nanostream 6055 noise ???

[LindaQ]

I just got my nanostream 6055 & I love it. I'm also using a 6100. When the controller is set on interval 1, the nano makes a clicking noise when it starts.
It does'nt do every time it starts, but often enough to startle the fish and sometimes it fairly loud. Is this normal?

It doesn't make any noise on any other controller settings.
Thanks.

[rvitko]

Yes, the nanos do click a bit on start up. I would chose interval 2 so the pumps idle rather than stop, it is better for the pumps, they go longer between service this way and the noise will be eliminated.

[LindaQ]

Thank you,
I appreciate your help.

Linda