Overflow Drain Bottom - Prefilter.....

[thecoolguy]

ok guys, so i have a question regarding the use of overflow chambers....

i have seen them used 2 ways:

1) to house the pvc piping and outlet (through bottom) to the sump - just like the TheTrust has his 250gal set up....

2) overflows full of filter floss and some bio-material elevated by eggcrate, with the outlet (bottom of tank) going to the sump

which way is better? i would say 99% of the overflows i see here in asia are done method #2......

logically, i thought i would set mine up version 2 also, cause what better way to pre-filter the water pre-sump then by using the overflow chamber?

i know i can be very wrong, and want some enlightenment! what are the good/bad of both methods?

 

[crashinc25]

I was hoping for answers to this question as well.

 

[thecoolguy]

well, found some answers to my questions.....seems like people are pretty much split on what route to take....benefits to both seems like...

one remaining question:

if one decides to fill up the overflow with bio-balls - in which case they may end up being 10-20% submerged at most - why does this become a nitrate factory? and is there any way to use bio-balls without the nitrate effect?

thanks for looking....

 

[crashinc25]

Ah, I'll just use them to house the pvc piping and outlet.

Good luck

 

[Volenti]

well, found some answers to my questions.....seems like people are pretty much split on what route to take....benefits to both seems like...

one remaining question:

if one decides to fill up the overflow with bio-balls - in which case they may end up being 10-20% submerged at most - why does this become a nitrate factory? and is there any way to use bio-balls without the nitrate effect?

thanks for looking....

Well the marine guys seem to be dead set against bioballs (in favour of live rock) siting that bioballs can collect detritus and become nitrate factories (which seems strange because that's the whole point of bioballs, to create nitrates)

If the bioballs are creating nitrates they are operating normally, though you could utilize filter socks or a pre filter (cleaned regularly) to prevent excess muck from collecting in the bioballs and creating more nitrates than necessary.

[edit] To clarifiy, you want to use mechanical filtration (cleaned often) to remove all the solid wastes from the water and leave the bioballs to treat the soluable wastes that the mechanical filtration can't remove, you then use water changes to keep the nitrate levels at acceptable levels.

 

[ercnan]

All filters are by design "nitrate factories". That's what they do. That's the end result of the process.
Some marine animals are very much more sensitive than fresh to nitrates, hence marine people using live rock, sand. They want nitrate reducing filters to save on expensive water changes and to keep highly sensitive animals.
As far as the anything in the overflows goes, it's your call. If the prefilter gets plugged, you have flood waiting to happen. I keep nothing in the overflow. My prefilter is in the sump before the water passes over the biomedia, that way if it does gets plugged, it just overflows on into the main chamber.

 

[Dr Joe]

Well the marine guys seem to be dead set against bioballs (in favour of live rock) siting that bioballs can collect detritus and become nitrate factories (which seems strange because that's the whole point of bioballs, to create nitrates)

If the bioballs are creating nitrates they are operating normally, though you could utilize filter socks or a pre filter (cleaned regularly) to prevent excess muck from collecting in the bioballs and creating more nitrates than necessary.

[edit] To clarifiy, you want to use mechanical filtration (cleaned often) to remove all the solid wastes from the water and leave the bioballs to treat the soluable wastes that the mechanical filtration can't remove, you then use water changes to keep the nitrate levels at acceptable levels.

NitrAtes aren't made they are a byproduct of the 'nitrogen cycle' (just a clarification), you can't "create too many" nitrAtes because your filter can only work up to 100% efficiency and that's not normally reached.

And what ercnan said too.

Some people put foam in the overflow stand to quiet the girgling sound that they sometimes make too.

Dr Joe

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