Query Re Use Of Carbon Containing Filters

Hi,
I have 2 internal filters that use a carbon type pad (interpet P1 & a CF1). I have always used the normal filter & the carbon filters, rinsing with fish water and returning them into filter, going on the premise when the carbon is no longer active that it will continue to act a physical & bio filter.

However, I am now wondering whether actually it begins to release some of what it has previously adsorbed. Opinions appear to differ on this.
I am wondering if I should only use the carbon filters occasionally when removing any meds or for the occasional clean up, rather than using them all the time - I wouldn't intend or afford to replace every few weeks!
do these cheap carbon filters release what they have picked up or is this insignificant amount of release?
Thanks

In theory the danger with carbon comes when something that is more readily adsorbed gets into the tank. This could be something in the air such as paint fumes, or medication. The theory is that the more readily adsorbed substance will push off what's already there. This is one reason that it is always recommended to remove carbon before medicating the tank - the main reason being that any unused carbon will also adsorb the medication.


The PF1 filter appears to have carbon sponges and plain sponges. All you need to do with this is swap the carbon sponge for a plain sponge.

It is difficult to work out what is in the CF1. Is it one cartridge that contains carbon and the algaway spheres, or are there two different cartridges? Since the algaway spheres won't do much as they also get used up, I would just cut the cartridge(s) open, empty them out and stuff sponge inside the bag instead.

Hi,
With the PF1 I have done exactly that, just recently - have 2 plain sponges.
The CF1, I hadn't investigated inside the pad containing the carbon - might cut into one for interest at least!

It didn't come with the media balls cartridge but I added my own bad of ceramic thingamys straight away (wedged in at the back). I hadn't noticed the algaway pad blocking particularly (I thought it seemed to wring out quite well!) but I will keep an eye on it. I may go for a plain sponge wedge in future then!

Thanks for the advice - think I will just use the carbon as and when required then (not expecting any paint or burnt dinner fumes, lol. - kids would argue the latter though  )

I've had a CF1 in the past, and cut the pad to remove the carbon.