Hah ok, so I was slow posting
The phone rang! I have to agree with Durb, your tank is far overloaded with the fish you have... I would strongly urge you not to get a "load more fish". If you like a lot of fish, maybe you could consider swapping out for some smaller fish. Plecos in particular have a really heavy load on a tank because they are like poop machines hehe. Clown loaches also get pretty big if they aren't stunted (up to 12" also).
If you have a test kit - test your water and post your results. Its possible that removing so much water and gravel vaccing caused a mini cycle.