I really think the whole pods
get chopped to bits idea is a bit blown out of proportion.
Sure I can see some of them getting chopped up but most of them are very small and I can see where many of them would be able to get past the impellers relitivly safely.
One thing I see would be that if/when power goes out will the 1/4" pipe from the refuge get filled with air? if so would the pull from the water flowing past the "Y" fixture be enough to syphon up the water from the refuge?
Also would the pump push water past this Y fitting or would the water end up flowing back down into the refuge?
I guess trying it out is the only way to definatly answer these questions.