i wouldnt buy either
if you feel you must have a 'phosphorous amendment' fish bone meal
if i were to buy a soft phosphate it would be 'calphos' but; i just dont need it
I've wrote before that I have guano here almost 2k laying about so I will use it, would like to cut it out in the future but I dont think it will cause issues? This is going outside and I have refrained from adding fish products, plus can't find fish bone meal commercialized in this country, the people eat much fish here but I think they just grind it all up with the other parts to make fish meal or something? Will try harder to source this in the future but I dont think this is a resonable option right now.
I probally wouldent be considering the rock phosphate either but I'm having issues sourcing rock dusts, so I thought I might add it for some mineral diversity. The whole phosphate industry is pretty disgusting.