Clean or replace bio media?

[meangene714]

I read somewhere that the pores of bio media can become "clogged" with dead bacteria after prolonged use. I guess this is why some manufacturers recomend replacing the bio media once in a while.

If this is true, could you boil the media, or soak it in a chlorine solution and reuse it?

Or maybe this is the advantage of using plastic bio balls, which have less suface area but never have to be replaced?

 

[jamzwayne]

Good question.
I'd like to know the answer to that (minus the use of a chlorine solution). The Chlorine solution is a definate no-no.

 

[RTR]

The massive surface area claims for many biomedia are likely valid, as they are based on the micropores and channels of their media. Those micropores will clog with dead biofilms over a time period related to the size of the micropores and channels. As bacterial layers develop, fresh cells will grow over old ones, suffocating those below, depriving them of access to both oxygen and nutrients, or in the case of facultative and obligate anaerobes, just nutrients. That growth clogs the pores and channels gradually but eventually totally. Home traetment cannot restore those pores in biomedia any more than it can to activated carbon whose sites are all loaded. Sintered glass and other microporous media has a finite life for the large majority of the surface area, after which its effective surface is much like that of similarly sized and shaped rock. Very few manufacturers admit this.

 

[daveedka]

.
Chlorine solution is a definate no-no.

Why is this? I've been using bleach and chlorine solutions for years with no problems. Is there something I need to know?

Dave

 

[jamzwayne]

hmmm...I have always been told...from day one...never use a house hold cleaning supply on ANYTHING that will be introduce to the water. (ever)

 

[TKOS]

Ahhh, but chlorine bleach can be used to clean tank things. First it will kill any potential bad bacteria or fungus. Then it can easily be halted by either massive rinsing or just good old dechlorinator.

But it should never be put into an active tank.

You shoudl never use any products that contain soap (often called Sodium Lauryl Sulphate) or ammonia near or in a tank. Soap is almost impossible to remove and can block the gills from accessing oxygen (spray soapy water on an earwig).

 

[meangene714]

The massive surface area claims for many biomedia are likely valid, as they are based on the micropores and channels of their media. Those micropores will clog with dead biofilms over a time period related to the size of the micropores and channels. As bacterial layers develop, fresh cells will grow over old ones, suffocating those below, depriving them of access to both oxygen and nutrients, or in the case of facultative and obligate anaerobes, just nutrients. That growth clogs the pores and channels gradually but eventually totally. Home traetment cannot restore those pores in biomedia any more than it can to activated carbon whose sites are all loaded. Sintered glass and other microporous media has a finite life for the large majority of the surface area, after which its effective surface is much like that of similarly sized and shaped rock. Very few manufacturers admit this.

Very informative, thank you.

 

[Blinky]

RTR, I did NOT know that! Eek! So the Aquaclear foam blocks I'm using in my AC 150 and 200 will become basically useless in time? How can we tell when something's becoming so clogged as to be ineffective - is there something visually that will tell you or a certain length of time they should be used, or do we just wait until the tank seems to need more cleaning than usual and take it as a sign that the bio-media is on its last legs? I've been using these foam blocks for... well... over a year anyway, and now I'm wondering if I should put new ones in (one at a time so the bacteria have time to move onto the new sponges of course) and replace them.
Does this also apply to Penguin bio-wheels?

 

[meangene714]

RTR, I did NOT know that! Eek! So the Aquaclear foam blocks I'm using in my AC 150 and 200 will become basically useless in time? How can we tell when something's becoming so clogged as to be ineffective - is there something visually that will tell you or a certain length of time they should be used, or do we just wait until the tank seems to need more cleaning than usual and take it as a sign that the bio-media is on its last legs? I've been using these foam blocks for... well... over a year anyway, and now I'm wondering if I should put new ones in (one at a time so the bacteria have time to move onto the new sponges of course) and replace them.
Does this also apply to Penguin bio-wheels?

Yeah, I've been using the Ehfisubstrat that came with my 2217 for about 3 years now. I think I'm overdue.

Good question about the bio-wheels.

 

[daveedka]

RTR may correct me if I'm wrong here, But The high surface area bio-medias like efhisubstrate are the ones that tend to clog. the less pourous, lower surface area stuff like sponges will rinse clean because the pores are big enough to allow it. To put this in perspective, the surface area of one litre of efhisubstrate is said to be roughly the same as a football feild. now think of how small and how many holes it has to have to accomplish that!!! With a sopnge, the surface area is more like a few square yards. so there really aren't small pores that can be clogged by dead bacteria, nor is it as likely that bacteria can clog the path of oxygen and nutrients for the other bacteria. So essentially it takes much more sponge or efhimech to do the same job as efhisubstrate or equivalent, but the sponge will wash clean and last longer. The thing to remember also is that you only need a certain amount of surface area for a bio-filter so despite the increased effeciency of the bio-medias, they aren't critical to have in most of our tanks. sponges and bio-wheels will do the job nicely.
dave