how does this sump work

and the most i can replace is 5 gallons because will thats the only amount of salt i have left.

 

I wouldn't worry about the nitrate in the sump, just do a change later when you have the salt.
I would rinse the bioballs once before you use them. you could actually remove them if you want. You don't need them unless you have ammonia.

 

i wont need the the bioballs? what can i put it there instead.

 

if you want you can put Live rock rubble in their. but wetdrys, which is what you have, are really for tanks with lots of fish not really reefs(I'm guessing you want a reef).
most reefers don't bother with them and just use the sump space for other equipment like skimmers. Since we have large amounts of live rock with surface area in our display tanks already wetdrys are kinda redundant.

 

oh anyway you think you can run me though the steps for this?

 

for what?

 

how to get this sump going

 

reread the posts in this thread they tell you how to do it.

you will have far more complicated pieces of equipment in this hobby then a fancy siphon and a pump

 

lots of reading 2 do.

 

so the fact that the pump is like 300 gallons per hour faster then the filter is nothing?