I have a FASTq files with size of appx 340 MB when I upload to Galaxy via filezila its size become 1.5 GB I have done it couple of time deleting and reloading. Then I also downloaded the file from Galaxy and compare side by side original file which was uploaded and the one after upload it is indeed different in size as I mentioned. I cannot explain this. Do You know what may be the cause of this difference.
I took a look at your account at http://usegalaxy.org and the larger fastq files. The content appears intact and complete for the one I checked in detail (dataset 117 in the history Jl_PB).
Is it possible that the data was compressed when loaded with FTP? Compressed fastq data, once loaded into a history at http://usegalaxy.org, is uncompressed as part of the upload process. This will impact file size. Other than that, I do not have an explanation for why this would be occurring.
If compression does not explain the difference, and you want to or have time, sharing the original data at an FTP site so we can try to duplicate could be the way to find out what is going on. Send an email to firstname.lastname@example.org with the exact steps used, the FTP URL, example data file name, and login credentials (unless is just anonymous FTP) along with a link to this post. (Don't post any of that info here, unless you don't mind the data being public, for at least the short time window you are granting access).
There are other ways to share the data - for example, loading it via FTP as usual then emailing us about it, being sure not to move the data into a history (meaning, leave it in the intermediate stage where the file is in the FTP loading area).
Hopefully we can solve this problem whether it is usage or technical issue. Jen, Galaxy team