genomic DNA from marine invertebrates

[Catherine Vogler]

I am trying to extract genomic DNA from a range of different marine  
invertebrates (crustaceans, molluscs, ascidiands, zoanthids,  
sponges...), but so far with mixed results. I have used Phenol  
Isoamyl Alcohol, Chelex, Qiagen DNeasy tissue kits and Promega Wizard  
SV kits. I have some problems with PCR inhibitors, and although the  
Qiagen kit seems most efficient at removing these, economical  
constraints are a bit prohibitive to keep using it. So i was  
wondering whether someone could advise me on alternative inhibitor  
removal methods, or has experienced similar problems when extracting  
marine invertebrate DNA and has found a solution.

And then i had a second question: as i will in the future be  
processing large amounts of samples, i am looking for a 96-well  
extraction method. Probably using a vacuum manifold, but then i came  
across the Qiagen MagAttract Plant Kit. Although it is designed for  
plants, could anyone advise me/have any experience on the possibility  
of extracting invertebrate DNA with it too?

Thanks a lot!!