I'm sorry that the Hydrogel-N did not work as expected.I am told that there are a couple of possibilities:
1) It needs to be mixed more aggressively and for a longer time. It really needs to be agitated.
2) It was too old. The technical sheet on the material says that it has a shelf life of “at least 6 months in an unopened container…” http://3x05x138oodi1m8k4h3gh952.wpengin ... olytek.pdf
Do either of these possibilities seem to explain what you observed?