Problem reusing yeast

I brewed 10 gallons over the weekend, and bottled 5. So i bought yeast for one of the new brews, and was going to try reusing the yeast for the other. The fermenter with the reused yeast hasn't started to bubble, so i was wondering if anyone can tell me what i did wrong, and how to fix it.

I took the trub and the little bit of beer in the bottom of the primary fermenter, and put it into some glass jars, and then let some of the particles settle out. I got rid of what settled out by transfering the liquid to other jars. Then i added some cooled boiled water with DME in it. After about 1 hour the jars started to bubble a ton and foam, so i know there was good yeast. So i had 2 fermenters with the same wort in each of them. I pout a vial of white labs yeast into one and it takes off within 8 hours, and the one with the harvested yeast that was bubbling in the jars does nothing. The only thing that i can think of, and it makes no sense, is that i only had one airlock, and the one with the reused yeast has a blowoff tube, which i have never used before.

Thanks for any advice that i can get.

I don't think the blowoff hose is your problem(though I don't know what is) I just did an amber ale with yeast I havested and it took off like crazy. I had to switch from an airlock to a blowoff hose because it was going so good.

It's only 8 hours...give it some more time...patience, Grasshopper!

I pitched the yeast saturday night. It has been almost 48 hours. That is why i guess i should go buy some more yeast now.