Headbandrocker.... Metanaturals is good and I also like the Botanicare Pure Blend Pro Bloom Formula it has an NPK of 1.5-4-5 So, those numbers are pretty close.
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I got a new bloom formula made by Blue Mountain Organics recently, it's called Flower Power, it has an NPK of 1-8-7. Since, it's filtered to remove sediments, it would probably work fine for you. BMO are the guys who make Super Plant Tonic.
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You can get this new (all organic) bloom formula on Ebay for $ 3.50 a bottle plus shipping - so, that's pretty fair. BMO always starts their stuff pretty cheap and lets advertising by word of mouth work for them. I don't imagine it will stay that cheap for long. Their SPT is a great product, (it was $ 4.50 a few years ago, now it's $ 6.95 - which is still a deal in my book), but probably a little chucky for drippers - it would have to be filtered for a drip system.
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Hope this helps..
Keep it Real...Organic....
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