Beneficial Bacteria And Filter Media

Hi. I have a cycled freshwater tank (set up a few months ago). It is moderately stocked. Total water volume approximately 150 liters (tank + sump + canisters). Tank has plastic plants and gravel (more like pebbles). Sump has pothos and lucky bamboo with roots in water. Sump also has a good amount of biomedia (ceramic rings and siporax). My canisters are in series as follows (in this order): canister 1 (mechanical) with course sponge and a generous amount of filter floss. Canister 2 (biological) filled with various kinds of ceramic rings and some bioballs. Canister 3 (an extra canister I had that I added in series to increase total system volume. Note: only one canister is actually plugged in and provides the flow. My question is: with so much surface area for beneficial bacteria to grow, do I have to worry about the amount that would be lost if I threw out the filter floss and replaced with new floss. Up till now I have only been opening the 'mechanical filter' canister every month or so, and rinsing the course filter sponge and filter floss and squeezing them in tank water. But I want to change the filter floss. Can I do that safely without affecting the balance of BB? Of course some might say, change the floss in increments (only a bit each time) and other similar suggestions. However for simplicity it would he much more convenient for me to just empty the compartment with filter floss and add new floss.
On a side note: I am changing the filter floss (and plan to change every few months) only because I've read people replace their filter floss. But honestly I haven't noticed any decrease in flow with my current floss. And it is never that dirty.
This brings me to another question: do I really need to replace filter floss? Or can I just wash it and use the same floss indefinitely? What will happen? Will it start falling apart? In the few months I've been using it, I haven't seen any degradation in the physical characteristics of the filter floss. Any info on this topic would be much appreciated. Thank you.

 

Paragraphs would make reading easier but I rince my filter floss maybe once a year and swap out one every 3 years or so.

 

My setup is not as big, and I only use HOBs. All of them filter floss and I toss them out and replace with new ones every week.

With your generous amount of filter floss and sponges, I doubt you'll run into any issues.

 

To me, you don't replace your filter media unless they are falling apart or too dirty and beyond cleaning/rinsing.

The filter media hold all your BB and you don't replace them unnecessarily.

But since you have 3 canister filters + sump filter, your filter floss is insignificant at all.

In fact, you can use your filter floss as your first layer of filtration (the first filter to receive the water intake) to trap all the debris.
And you can replace it at any time when there is too much debris in the filter floss.

By the way, you have too many filters for a small tank with moderately stock.
I guess all your filters don't really have much BB.
For BB to grow, they need much food (more ammonia and nitrite), which mean bigger tank with more fish especially bigger fish.
Actually 1-2 canisters will be enough since you have a sump filter.
Anyway, this is up to your preference.

 

Thank you all for your replies. Lajos, when you say 'falling apart' what exactly is meant? In my readings I have come across this term several times (talking about filter floss). But how exactly does filter floss fall apart? It is not a single item... it is just a bunch of synthetic fibers bunched together.. so by definition it has 'fallen apart' before even using it. If you know what I mean. So in your opinion how would I determine it is falling apart?
Thank you.

 

Thank you all for your replies. Lajos, when you say 'falling apart' what exactly is meant? In my readings I have come across this term several times (talking about filter floss). But how exactly does filter floss fall apart? It is not a single item... it is just a bunch of synthetic fibers bunched together.. so by definition it has 'fallen apart' before even using it. If you know what I mean. So in your opinion how would I determine it is falling apart?
Thank you.

What I meant is when the filter floss is becoming too loose (instead of one piece of filter), where it can't trap the debris any more. That's when the filter floss is becoming useless or of little use.

As you know, the main purpose of sponge or cotton floss, is to trap the debris when the water passes through them.(mechanical filtration).

At the same time, the filter floss also serves as a biological filter to hold the BB.
So, it serves two purposes.

But when it falls apart, it lost it's function as a mechanical filter in trapping the debris.

 

Thank you all for your replies. Lajos, when you say 'falling apart' what exactly is meant? In my readings I have come across this term several times (talking about filter floss). But how exactly does filter floss fall apart? It is not a single item... it is just a bunch of synthetic fibers bunched together.. so by definition it has 'fallen apart' before even using it. If you know what I mean. So in your opinion how would I determine it is falling apart?
Thank you.

It will unravel a little and just disintegrate eventually. I change mine every 3 months or so. Didn’t effect bb. Have a canister with 4 trays with ceramic rings etc. so the floss is more for polishing water not holding the bb.