Pre-filter on uptake pipe
I own one of those aquariums with a in hood filter that uses an uptake pipe. I have replaced the stock strainer (ie plastic nob with long rectangular thin holes in it) with a sponge pre-filter. However, after a while, I noticed the amount of water goiing up the uptake pipe has significantly decreased.
I tried cleaning the pre-filter but it still hasn't helped increase the uptake. The main problem is I'm hearing a slight rattling noise which I'm guessing is the magnetic impellor moving without any water around it.
I guess maybe whereever there's smoke there's fire, so I just wanted to ask, would I be damaging my motor/impellor (whatever) if I left it like that? Though atm, I don't seem to see a problem with the stock one since its not a sand base so there's less chance of sand building up in there.