When you put your siphon in the fermenter be sure that it doesnt touch the very bottom. Keep it about an inch from the bottom. When the level starts getting low, tilt your bucket while still keeping the siphon from the bottom.
You should look into upgrading to a glass carboy or even the plastic "Better Bottles".
I hated using buckets. I have brewed close to a 100 batches and have only got 1 infection and that was with a bucket. The smallest scratch will harbor an infection.
Sanitize, Sanitize, Sanitize!!!!
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