I got mine at premiumaquatics.com . The product is called DT's phytoplankton. I think the guy that runs the show there cares whether he is sending you a fresh product or not. They only keep so much on hand so sometimes hes out of stock. You'll only have to wait a few days for him to get more in. He sent mine on a wednesday and i got it friday via 1st class mail. The stuff only lasts like 7 days in normal temps. 6 months in the refrigerator. You feed your tank by pouring the liquid in the tank once every few days. keep your skimmer off for a few hours after feeding.
A couple ways you could do this.
1. Buy DT's. buy larger bottles and put in refrigerator for the unused portion. The phyto should stay effective for at least a week or two before you use it all up.
2. Buy concentrated paste form of phyto's. You can get them from Brineshrimp Direct. I believe they called it Cryopaste. Squeeze out a pea sized quantity and mix in a cup of water and feed to your tank.
3. You can culture your own. Both Brineshrimp Direct and Inland Aquatics sells phytoplankton cultures on a petri dish. Follow the instruction to activate phytos and start culturing. While you are getting the culturing kits, ask them for culturing media and their instructions too.
If you decided to dose phyto's on a long term basis, the most economical way to do it would be culturing your own, or use cryopaste.
