I have done genome assembly on an interleaved fastq file using many different assemblers (Velvet, ABySS, Minia, SPAdes, etc.) and have the "contigs.fasta" file from all of them. I have run over 50 assemblies with different parameters and options in each of those assemblers, now I have processed each "contigs.fasta" file using QUAST. I know that the length of the genome I am trying to assemble is originally 200,000. However using QUAST the "Total Length" and "Total length (>= 0 bp)" I am getting for 95% of my assemblies (i.e. contigs.fasta files from different assemblers) is near 390,000 all the time. What is the problem? Does "Total Length" in QUAST refer to something different? Why can't I get any length value near the expected 200,000? I have experimented with tons of k-mer, coverage-cutoff, expected coverage value combinations!