Lots o' poop. Overstocked?

[LIBPA]

I have a lightly planted 20 gallon tank with 16 neons and 2 austrailian rainbows and a zig zag spiny eel who will be put into a much larger tank next month. I do a 20% change mostly twice a week, sometimes i do one because im "busy".(lazy) Anyway there are piles of poo on the sand in my tank, I try to get as much up as i can. Its difficult because of the plants and decor. I was wonder if its ok to have a lot of poo on the bottom if i keep up on the bi weekly changes.
Thanks

 

[plah831]

you might want to increase the size of the WC's from 20% to 50%. I have a slightly overstocked 29 gal that I have to do two to three 50% WC's on EVERY WEEK to keep up with the waste (until I can upgrade to a 55 gal). Leaving the poop there will only result in more ammonia/nitrite/nitrates.

The only time leaving poop is OK is when you have densely planted tanks and plant-specific substrate. see this thread for why
http://www.aquariacentral.com/forums/showthread.php?t=81989

 

[LIBPA]

Thanks that helped