Grimer location

Good question. I'd like to know as well.

If it wasn't for eggs and the buddy system I never would have been able to Muk (who I love using by the way).

I evolved one a few weeks ago just for the pokédex entry. Now I'm kinda regretting it, because I just caught one with 1024 CP and 91% IV and there's like no way I'm evolving it anytime soon. Learn from my mistakes. These things are rarer than Snorlaxes.
Btw, I'm not sure where you from but you should check thesilphroad's nest atlas. Might help.

The pike in long beach California is known for grimer .. Went there twice and caught like 10

Where I live it seems to spawn mostly on suburban streets. Personally I got lucky and hatched 2 Grimers in a row from 5k eggs. To my horror Muk received Lick/Sludge Wave.

After 2,5 months I managed to run into enough Grimers to evolve a 2nd one and went with a hatched lvl20 74% IV one because I didn't have a better alternative. This time I rolled Poison Jab/Sludge Wave which is decent.

I'll probably have to use the buddy system for the power up candies since I run into Grimers so rarely nowadays.

I also have a 132cp 98% IV Grimer that I dream of some day evolving into a beautiful Muk with Poison Jab/Dark Pulse.

I found Grimer in random places downtown. Can't remember seeing one anywhere near the river where I spend most of the time and catch most mons, doesn't seem to like water.

Got 2 Muks so far 98% and 91% iv's when we had the buddy promotion for Halloween, I racked up more than enough candy to evolve the 2nd Grimer. Hopefully they do another buddy event soon. Both mine know Lick/Gunk Shot, wish it was Poison Jab though:(

From my experience they can spawn everywhere except near water. But they are rare. I manage to catch like 30 though. They are as rare as pikachu or charamander for me but not like porygon, aerodactyl or other superare things

Muk is the only remaining empty Pokédex slot I have, besides the regionals and the ones not in the game yet. I've been playing since about a week after the game came out and have seen exactly two Grimers: I caught one with a CP of 16 this month and made it my buddy for several weeks. Then I finally hatched one to get the rest of the candies I need. Unfortunately, the one I hatched has 75% IVs, so I'm going to hold off evolving it for a bit longer. (By the way, my spouse has hatched five Grimers during the course of the game, and we pretty much always visit the same stops. It's maddening.)

Yeah I have the same question because I have to evolve a grimer for meltan field research. Buddy farming isnt working fast enough