question about fish

Question
i own a 35gallon tank(50in(L)*20in(H)*18in(width)).i have 2 kissing gourami,2 snake skin gourami,1 golden gourami,1 pleco,2 platy,1 rainbow shark,1 molly,1 snail,1 eel.all the fish are small.i use 2 inch sand.i recently bought an sponge filter.my question is it neccesery to still have the UG filter along with the new sponge filter.
my second question my friend who lives next door is changing his aquarium from 55 gallon to 150 gallon.he wants me to keep his 3(3inch) pacu in my tank for 1 week.can i keep these fish along with my current stock.are is it going to kill all my fish.my friend says they are flake feed and wont bother my fish & he also told me he will get a tank seperator just in case.

Answer
Hello,

About the pacu: most fish will eat anything that will fit inside their mouths, including other fish. I would definitly recommend having a tank seperator if you will be watching a pacu.

I also recommend continuing to run both filters. Sponge filters are not always the most efficient filters, because they don't have carbon or biological filter media, so its better to have two and be safe.

I hope this helps.

Regards,
Stephanie