What can be used as a substitute for what? Where can I find these things in Hamburg (if I can find them at all in a store)? I am a non native living in Germany, wanting to start organics (thanks dankohzee and InTheGarden, your Starter Mix and Easy Organic Soil Mix guides/walkthroughs were awesome) with little first hand experience in horticulture. Being an immigrant with poor command of the German language, searching Google for shops in Hamburg to source even the basics has been a brain frying experience (though I am part way there, I have peat moss (Torf, Tomatendünger -- von Bauhaus gekauft), worm castings (Wurmmist -- von growland gekauft), perlite (Perligran -- von growland gekauft), compost (von OBI gekauft), and I know where to get bat guano (growland))*. My partner is German, but doesn't care at all about growing (dank) and appears to have no interest in helping me learn this stuff -- which is fine, she would probably just get frustrated too, on account of not knowing what many growing mediums, additives, etc are in English. It would just be the blind leading the blind. Anyway, I'm posting this in the hopes of someone speedily replying with all of the information I'm after. Such as -- can powdered spirulina be used as a substitute for kelpmeal? Can I get fish sticks (a pellet feed for pet fish, not just thin fillets) and grind them up into my own fishmeal? The closest I have found so far to anything like alfalfa meal is a powdered instant porridge for bunnies -- would that suffice? (I will have to check back at the local pet store (Futterhaus) to see what that stuff is made from.) Are there people that frequent the forum that come from Hamburg, and if so, do you have any idea of any stores that sell rock dust (steinmehl/ursteinsgemehl), kelp meal (seetangmehl), or alfalfa meal; are there any fishing shops in Hamburg (as I am guessing that would be a good place to get fishmeal/fischmehl from)? (I don't have a credit card. Buying online is not an option.) Thanks for reading if you got this far. *edited because I forgot a parenthesis