Not sure what you have available over there, but here I get Dogs Today, Your Dog and Dogs Monthly. Dogs Today is full of good reads, and they do overseas subscriptions too... http://www.dogstodaymagazine.co.uk/
Dog Sport Magazine?
I used to read The Bark but quit once they started plastering their political preferences in the magazine. Modern Dog is neat to look at all the expensive products I will never be able to afford LOL.
Clean Run is great if you're into agility! There's also a Canadian one called Dogsport that covers all different dog sports. Less involved how-tos than CR but definitely more involved training and what not than DF.
For a general more pet dog type magazine, BARK is really well done. I'm on the fence about them though because they tend to be a bit AR-y (tend...maybe more than that LOL they can be pretty AR at times). AKC's Family Dog is similar to DF but much better, more detailed and not quite as ad heavy (I swear DF is more ads than anything). Whole Dog Journal often has good, interesting and in depth training and care articles plus product and food reviews and no ads. It's very much positive, pet dog type training advice (some of it is quite good but what it is) and holistic/natural minded care though, so if those things don't interest you it may not be for you. I think tend towards the AR-y at times too.
Not all types of blue-green algae are toxic, some can be quite healthy as a supplement. Were they referring to spirulina? If so, it's considered a "superfood". And is found in quite a few dog supplements.