What causes the foam in a hot tub to turn mushy?

[Vinny]

Well, I'm battling ants in my house and whenever I open the hot tub cover. My tub is located not that far from my house so I figured the ants where in the tub. I opened all the sides expecting to see a colony of millions of ants ... Nope! Just a FYI, the tub is 9 YO.

What I did find is evidence that I may have had a mouse - round hole in the foam along with scattered little pieces of foam and a round hole in the plastic in a different location - no nest that I can see and by the filter mushy foam. What would cause the mushy foam? The area was a little wet and I suspect my cover may be the culprit as it drains on that side whenever I open it.

Should I buy the minimally expanding foam and refoam the area? Should I even waste my time?

[clover]

Vinny, the only thing I know of that is going to make foam spongy is water.  Take some of the foam and squeeze it to see if you get moisture out of it.  IF that is the case, it is not the cover, but you have a leak, keep digging until you find warm water which is closer to the source of the leak.

Ants love the moisture, any place you see them spray where they are, where they travel, and close and seal up any and all little access holes where little critters can get in, steele wool works great.  The size of the little bits of foam are the size of the mouth that dug it out.  Mice and chipmunks are the most common critters, you gotta lock them out.

[Vinny]

Vinny, the only thing I know of that is going to make foam spongy is water.  Take some of the foam and squeeze it to see if you get moisture out of it.  IF that is the case, it is not the cover, but you have a leak, keep digging until you find warm water which is closer to the source of the leak.

Ants love the moisture, any place you see them spray where they are, where they travel, and close and seal up any and all little access holes where little critters can get in, steele wool works great.  The size of the little bits of foam are the size of the mouth that dug it out.  Mice and chipmunks are the most common critters, you gotta lock them out.

Yeah, I thought it was from a leak but was hoping it was from rainwater!  I don't think it's much of a leak it is as I don't see evidence under the tub and it is around the filter area but I guess I should keep an eye in case it gets worse. ( I know I'm being lazy!) I didn't find any ants (they may be in my cover ... that's getting replaced soon ... waiting for delivery) and the only sign of a mouse was a hole in the foam. I kind of remember a long while ago I was in the tub and heard something on the other side of the shell and I thought "mouse", did a lot of banging on the tub and never heard anything again. Didn't find poop or anything like that but did find what looked like puffed wheat along the bottom of the tub in some areas.

I forgot to add ... at least the foam is not mushy from mouse urine!

Thanks for your help!