I need help

whats your current team?

 

volcarona is an excellent pkmn though. ev training is a breeze with the power items you can get with battle points.
you should take a look at all your pkmn and their natures, and see how their current stats are. ev training is rlly inevitable if you want to be competitive. you have to exploit their strongest areas and give them correct moves to match.

what stats and moves do you currently have? whats your goal with each Pokémon (where do you want them to be)

 

Krookodile is a good selection also, Because of its access to Moxie. I'd suggest that you put A life orb or Choice Scarf on it, then Use Earthquake, Stone Edge, Super Power, and Crunch

 

You could train a Blastoise. I had one (I gift it to my cousin) with escald, ice beam, rapid spin and protect, with ev's in 252 Sp Def, and I think it was 200 Hp and 52 Sp Atk, but I'm noy sure, with the nature that reduce attack and increase Sp Def and with leftrowers.

 

I good strategy is is to have a Fire, Water, and Grass type on your team. They work well together. I hope this helps

 

4 of the 6 have a major weakness to ice. More balanced types would be best. As red said, keep a water, fire and grass in your team. Keep Hydregon, every team needs a dragon. And one more thing, never waist the ability to have a type advantage. You should lean toward multi-type Pokémon and the ever flexible normal types, like Snorlax or Porygon-Z

 

Just have one type that has an advantage to another, don't stick to just one type 'cause if your opponent has the type advantage over most of your team, you're dead. Take me for example, my team's majority is weak to fire, poison, ice, and electric. Having one fire, water and leaf type also helps.

 

I think its also important a electric Pokémon able to avoid ground attacks or to learn different types attacks that cover it (For the second, the example could be electivire. With Ice Punch you can K.O. ground types Pokémon.)