TheWiz

Recipes 

I'll go with Yoop's answer and also ask if you are fermenting in a closet. I was for a while and was also getting a plastic taste. It wasn't until I purchased a fridge to help with temp control that I got great beers. I was just fermenting at too high temps.

chrryghst

Recipes 

Yes, I am fermenting in a closet. I will admit that my temperature control isn't very good. I keep my thermostat below 70 but I don't control the sharp temp increase due to fermentation activity. I don't have space or money for a fridge, but I'll try the swamp cooler method next time. Also, I'll make sure to cool the wort to 65 before I pitch.

Thanks for the advice everyone! I've got a lot of new things to try to avoid that weird taste. Oh, I'm also going to make a yeast starter for the first time, just in case its an off flavor from under pitching.

ChrisJPassarelli

Recipes 

I'd recommend against distilled water! I'm pretty sure you need the nutrients and minerals in spring or other water for yeast prolification, whereas distilled doesn't give it anything to work with.

Besides that, it all sounds like good advice. I'm grappling with similar issues right now, with a persistent off flavor... best wishes.

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Browncouch Brewing
Primary 1: Lucky's Wheat Ale (1.0)(WLP 320)
Primary 2: Lucky's Wheat Ale (1.1)(Wyeast 3068)
Bottles: Tupelo Mead, Berry Porter, Mt. Hood Single-Hop Pale, Toasted IPA, Honey Oat ESB, Lucien's Amber (1.0)
[B]On deck: More Lucien's and more Lucky's.

WhineinAlbany

Recipes 

The water shouldn't matter since it's an extract brew. The extract itself should have nutrients from the water it was made from.