larryglass25 asked:
My chain is so covered in gunk that I’m debating whether I should spend $20 on a new chain or $20 for one of those chain cleaning tools you attach to your chain to clean for you. I got my bike used so I don’t know how old the current chain is.

It doesn’t sound like the bike has had a real good maintenance schedule. Check your gears (chain rings, cassette) and find out how bad there worn and if there not bad then I’d just replace the chain, if they are bad then you’ll need to replace gears and chain.
If you don’t want to go to the expense of new parts just clean the old chain and put it back on because that chain matches the gears you’re using.
I wouldn’t put a new chain on old or worn gears because it will just create problems with the new chain jumping off the gears because the new chain will not seat properly in the old gears.
As far as the chain cleaning tool goes, I wouldn’t bother with one. I had the Park Tool Cyclone Chain Scrubber and all it did was make a mess.
If the teeth on the gears look good i would go with a new chain and some chain lube. Always clean your chain before adding any oil, if you don’t the oil will wash the grit into the pins and rollers.