Replacing Fluval Filter Pads

[Kaidonni]

I've had my Fluval tank in operation about four years now. Last year I replaced one of the main filter pads, but I believe I caused an ammonia spike/mini-cycle that may well have contributed to the loss of a number of my fish. I now have to replace the other pad as it's getting thin in parts, and has been in for four years and two months, give or take. To be entirely clear, I'm not talking about the pad that fits in the middle (replaced every two weeks), but the two main ones either side.
 
I've got Seachem Prime which detoxifies ammonia so it's still available for propogating the new bacteria and keeping the remaining pad from being completely overwhelmed, and with over-dosing it can detoxify nitrites, but the idea of over-dosing for any extended period of time does not sit well with me at all.
 
I had an idea of how to possibly avoid being far too reliant on Prime and on water changes during this change over of pads - by placing a third pad in the tank (not in the filter), possibly wedged behind the filter against the glass (not blocking the direct flow of water through the filter). If I were to soak this pad in water removed from the tank and muck from the filter every week, would it assist in any effective propogation of the replacement bacteria? Since it wouldn't be going in the filter until after a few weeks at least, could it potentially expose the fish to ammonia or nitrites through any muck being caught in this pad, or wouldn't it make much difference since I wouldn't have yet removed the older pad from the filter?
 
I'm aware that the bacteria necessary to the nitrogen cycle are on every surface in the fish tank, so was hoping I could seed this new filter pad for weeks prior to the replacement, avoiding too great a net loss of the bacteria.
 
Thanks for any replies.

 

[paradiddle]

What media are you using? filter pads are NOT media, they are to catch particles in the water. (mechanical)
 
Replacing ALL (dont recommend just incase) foams shouldnt affect your tank, the bacteria lives in your actual media (bio balls, ceramic noodles etc)
 
You should look at cleaning the pads regularly, even if its just swilling it round excess tank water to clear it up a bit.

 

[Kaidonni]

I clean the pads every single week. The pads I'm referring to are the Fluval 2Plus foam pads (I don't use carbon in case I ever need to use any medication), which last a very long time, but the second and original pad is getting to be thin and developing holes. I replace the polyester pad (the middle one of the three pads) every two weeks. I'm under the impression that the foam pads are for both biological and mechanical filtration; the polyester pad isn't sufficient enough since it needs replacing so often.

 

[Kaidonni]

Anyone? This is really important for me to get right, especially after the last time...

 

[DrRob]

Personally, don't replace it. It's half of your biofilter.
 
If it gets thin, add a bit of ceramic media, or some more foam, if your pad has got thin then you'll be able to fit more in and you can gradually chance over. Generally I'd expect foam to last for many years though. I get sheets of pond filter foam (comes in mixtures of grades, the non shaped stuff is easier to add into filters) that don't cost too much and give you enough to last for ever for most filters. I generally end up using it for stuff like vibration reduction as I have lots left over.

 

[Kaidonni]

So it would be advisable to cut any new foam into half and add it as necessary, combining it with the deteriorating pad?

 

[KirkyArcher]

Agreed with Dr Rob the sponges actually ARE filter media, and do contain lots of the Bacteria, Cleaning should be never anything more than a wringing out and swirling around task (in either removed tank water or as a second option in conditioned water) to remove the heavy trapped solid bits of waste to permit better flow through the entire filter, It's always advisable to just replace/renew one element at a time, so I'd just leave the most intact one in situ and put a new one in on the other side, and do an extra water change per week