Please advise my sentence

I want to complain my supplier that deliver the low quality of goods to me.

Dear Luew,

The fish from container no.MEAU1234443 that you delivered to me and QC found decompose fish during inspected last week. This problem was happen same as shipment of July which the fish caught in xx islands by long line method and the fish mixed from various fishing vessel in one container, I have checked and found the fishing date had the previous year and the beginning of this year.
For decompose fish, the production will plan to produce product and find the lower market for support low quality fish, please note it takes a long time to clear them more than normal fish.
By the way, you loaded fish from 10 fishing vessel, It's very hard to use document for export, I can not separate every fishing vessel on loading process to match with quantity that showed on shipping document. Please avoid to deliver mix fish from several fishing vessel, not over 8 fishing vessel per 1 container and kindly ensure the quality before deliver to us. You are a best supplier for me, I feel certain that you should support the best quality fish to us every shipment.