I have precious axolotl eggs a couple of days from hatching (they're already thrashing around in the jelly) so we've rigged up a shrimp hatchery. The problem is the pump connected to the hatchery - it seems to be churning up the water to an alarming degree. It is designed for a tank of 19 litres so is it just too strong? Should I just not aerate at all or get a smaller pump? Please help.