Stinky rainwater collection

[sunfire]

Hello all.

Just want to be sure I'm not making a big mistake here.

I collect rainwater to use for my orchids. I had been keeping this in 5 gallon pails which has worked very well but not convenient. I recently purchased a 30 gallon barrel and set it up with a pump hose dispenser and filled it up after the last storm. The barrel is inside and I use buckets outside to collect the water so it's kind of a big deal that I was able to fill it up.

I should have bleached the barrel and the pump first in retrospect as the inside grew a whitish biofilm, the water is a bit cloudy and stinky. Never happened in my pails and I had one unused for over 6 months. I used Physan at a little over the bird bath levels. The water still smells and is cloudy but the biofilm seems to be gone. I probably should have just used bleach rather than physan but oh well.

I'd like to still use this water. No big storms in the future but I have my eye out. Am I making a big mistake?