easiest, cheapest way is to get plant weights, the little rubber band like holders that weigh down plants, i went to my lfs and asked about them, they don't sell them they reached in thier plant tanks and gave me several for free, then just clip em on and let the cuc sink to the bottom, they also make the cuc stand on end lol so its like a serving tray
I peel the skin off of mine and i dont like blanching or nuking them either, i just cut a slice and let it sink, my plec and clown loaches love it