Media In A Flter, The Path Of Least Resistance?

[fry_lover]

Hi All

I've got some Seachem Purigen media (which is in a Seachem Media Bag) and i have been using this in an internal Fluval 4+ filter.

With the bag full of the Purigen it takes up most of the space inside the filter housing but not all of the space

The thing i am wondering is....... do you think a lot of the water passing through the filter will "take the path of least resistance" and just by-pass the media? Obviously not completely by-pass, but mostly by-pass?

do you think i would be better off putting the media in one of the trays in my externals and surrounding it with sponge?

PS - the media is not dependant on the flow rate (i.e. like certain nitrate reduction media is)

Thanks

 

[rabbut]

The water would mostly by-pass the media in the internal filter, so yes, if you use it, add it to the exturnal filter. What are you using it for? Also, what is it removing, other than nitrate? I have found that most medias that remove nitrate also remove ammonia, and thus un-cycle the tank Make doubly certain that this media is safe by looking to see if it removes ammonia or nitrite before putting it into service

All the best
Rabbut

 

[OldMan47]

Any media that you really want the water to go through should be in the main flow path. If you could control how much goes through and how much bypasses, as is done in some hydraulic systems, you would get the right flow to go through but just leaving it to chance that water will pass through is not likely to get the media involved in the process very much. As the flow resistance of that media builds up over time it will get even less flow. I would try to get a full flow path but be careful not to plug up the filter's flow path by restricting it too much.

 

[fry_lover]

The water would mostly by-pass the media in the internal filter, so yes, if you use it, add it to the exturnal filter. What are you using it for? Also, what is it removing, other than nitrate? I have found that most medias that remove nitrate also remove ammonia, and thus un-cycle the tank Make doubly certain that this media is safe by looking to see if it removes ammonia or nitrite before putting it into service

All the best
Rabbut

Thanks for your reply Rabbut, i think i will move it to the external, will see what other's say as well though.

As for the Purigen, it doesn't really remove nitrate as such, but can help (apparently) consume organic waste and thus reducing nitrate build up. I am still in the early days with it, as an experiment. I have PM'd Rdd1952 some info on my findings, i will send you the same PM, you might find it interesting. From my experiments with it, it is not reducing the effectiveness of the normal biological filtration (not to any degree of significance atleast), as evidence by ammonia and nitrite readings, you will see what i mean from the PM!

Any media that you really want the water to go through should be in the main flow path. If you could control how much goes through and how much bypasses, as is done in some hydraulic systems, you would get the right flow to go through but just leaving it to chance that water will pass through is not likely to get the media involved in the process very much. As the flow resistance of that media builds up over time it will get even less flow. I would try to get a full flow path but be careful not to plug up the filter's flow path by restricting it too much.

Thanks OldMan i was thinking that was the case. I know some water is passing thorugh the media and some of the media is turning a light brown (from brilliant white colour) indicating (according to Seachem) that it's removing organics from the tank.