My husband and I recently acquired a hot tub. We would like to install every ourselves but are totally green on the subject. So, we have decided to at least purchase the materials and have an electrician just hook it up to the box. What type of wire should we buy. I know it is 6/3 but the hardware stores sell both aluminum and copper. We have received conflicting info from both. Generally the folks in the store are not licensed electricians and that makes me a little nervous when one says sure use this or that. There is a hugh price per ft difference and we need 70ft so I cannot afford to make a mistake here as we buy it we are stuck with it.

Thanks,
A

Why don't you ask the electrician what he needs. I am sure he will offer professional advice.

We have some great people here. I asked to have this moved to Electrical where tkrussel will see it.

Before anyone can recommend a wire type and size, the load in amps or watts of the applaince is necessary to determine the correct size.

In other words, how do you know that #6-3 is the correct size wire?

We asked at Home Depot and Lowe's. They have a hot tub "kit" and we were there comparing prices and asking questions about how to install etc. We were told to use this size for 50 amps

OK, For a 50 amp circuit, #6-3 with ground Romex (4 wires) with copper wire can be used as it is rated to carry 55 amps.

#6 Aluminum is rated 50 amps, but must use what is called SER cable, which will have a total of four wires, just as the Romex will have, two hots, one neutral, and one equipment ground.

So either, copper Romex cable or aluminum SER cable may be used for this 50 amp circuit. Just with the aluminum, must be sure to terminate the wire properly, such as wire brush the metal, and apply anti oxidant compound, and just as with copper wire, torque the terminal screws to proper values.

See the attached manufacturers recommendation for terminations of aluminum wire.

I am so IMPRESSED, tkrussell!