Working on my first ultimate filter/ wet dry

Will it be ok if i use some sponge
s..
I bought some srubers for a dollar still need to buy more

I was thinking top 2 slides ill make them with sponges and srubing sponges
And the last one bio balls ..
Will bioballs work better under water or water dripping on top of them?
I made my over flow and works fine but my pump its a little bit faster.
http://www.youtube.com/watch?v=dvQD05ta7eE&feature=youtube_gdata_player
Any advice will help thanks

Will it be ok if i use some sponge
s..I bought some srubers for a dollar still need to buy more

I was thinking top 2 slides ill make them with sponges and srubing sponges
And the last one bio balls ..
Will bioballs work better under water or water dripping on top of them?
I made my over flow and works fine but my pump its a little bit faster.
http://www.youtube.com/watch?v=dvQD05ta7eE&feature=youtube_gdata_player
Any advice will help thanks