Got mines and started feeding the vitamin flakes to my Red Cherry Shrimps. They got deeper red. I feed very heavy due to large quantity of shrimps (they eat 4 algae wafers every day proably more if I gave more). Haven"t tried the fishes yet due to both being very fine powder now (thanks usps!). Mines just look like I'm purposely mixing powder to thicken the water! Will try the spirulina as soon as I get done with the vitamin flakes! Thanks for the sample and I'll report in later again!