my spa looks like a washing machine

[flajoker]

We get a pile of foam every time we crank up the jets...haven't used in 2 days, walk out and turn on jets and might well throw the cloths in.
Would this be why you need to empty tub and refill after one month?

[stuart]

We get a pile of foam every time we crank up the jets...haven't used in 2 days, walk out and turn on jets and might well throw the cloths in.
Would this be why you need to empty tub and refill after one month?

Only after the first month but, yes

[Dr. Spa™ Ret.]

Most likely your washing machine is exactly what caused the problem.

Most, if not all washing machines don't rinse out all the soap, and soap from swim suits is the frequent cause of such hot tub foam....

[Mendocino101]

Changing the water is the right thing to do....If everything is in balance than your problem as DR suggests is coming from the washing machine...have everyone who uses the spa do a rinse only for the suits they use....it will help....and no suits is even better....

[Hammerhead]

....and no suits is even better....

We're in the same washing machine ... I mean boat.  I will start draining the hot tub tonight after work.  We are in our hot tub every night and as long as my wife and I are in (without suits) the water remains crystal clear.  We were cruising along after 4-weeks in clear water until my son's friends came over in their laundered trunks.  Worse foam we've ever had and it appeared the next night when I went to get in!

[wmccall]

We were cruising along after 4-weeks in clear water until my son's friends came over in their laundered trunks.  Worse foam we've ever had and it appeared the next night when I went to get in!

Bingo, Boy's trunks is usually the cause. If weather prohibits you from changing water,  I recommend foam out products and a partial water change (See past threads for foam out advice)