HELX-13/K1 verse Foam in Canister Filters

[Bradders]

Hello,

Well, here is a question that is causing me to scratch my head - something for the more technical of you out there to help me finalise! (Yes, I know I am obsessed with filters! )

In the Oase Biomaster (but it can be any canister filter with trays for media), some trays come with 800ml of HELX-13 plastic media, and some trays come with 20PPI foam. Now, my question is whether 800ml of HELX-13 (similar to K1) will be as good at providing a surface area compared to the sponges - which I measured the sponges to be around 70 square inches in size when you take away the cut-outs.

The sponge is the easier part of calculating surface area per volume. But how would one calculate the surface area that HELX-13/K1 media provides at 1 litre, 5 litres, 10 litres etc? I did a rough calculation that 800ml equates to 49 square inches using an online calculator - but that might be for liquid, so I'm not sure whether that would be a fair calculation.

Does anyone have some experience (and a technical mind!) for working this little puzzle out?

Thanks,
Brad

 

[fredi]

I recently started a new tank with 2 Eheim 1200xl’s used 30 ppi foam 50mm thick in all trays
Seeded with foam (trays) from established tanks, took 1 week to reduce 3ppm ammonia to zero measurable
I have used a multitude of different media over the years, can’t beat 30ppi foam (for cost/efficiency) imho
Again imho, the effective surface area of your media will change over time, clearly, starting with more is better, but more expensive in terms of purchasing media and running cost of fliter/s
I like to use 2 filters so only one at a time is ever “messed with”
Flow is king, maintaining flow will maintain filter efficiency 👍

 

[Bradders]

I recently started a new tank with 2 Eheim 1200xl’s used 30 ppi foam 50mm thick in all trays
Seeded with foam (trays) from established tanks, took 1 week to reduce 3ppm ammonia to zero measurable
I have used a multitude of different media over the years, can’t beat 30ppi foam (for cost/efficiency) imho

Yeah, my sense tells me this may be the answer. But still interested in how to compare K1/HEL-X surface area when compared to the same volume (20PPI or 30PPI) of foam! It's frying my noodle!

 

[fredi]

Yeah, my sense tells me this may be the answer. But still interested in how to compare K1/HEL-X surface area when compared to the same volume (20PPI or 30PPI) of foam! It's frying my noodle!

I am not sure that the 2 media are “equivalent” in effectiveness, in terms of surface area
If the k1 is kept mobile, it will require less cleaning
However unless fine media is present, particles will flow through the filter, if fine media is present, it will block relatively quickly

 

[Bradders]

I am not sure that the 2 media are “equivalent” in effectiveness, in terms of surface area
If the k1 is kept mobile, it will require less cleaning
However unless fine media is present, particles will flow through the filter, if fine media is present, it will block relatively quickly

Interesting. The Oase does have a 45PPI pre-filter that 'protects' the media in the main unit. The pre-filter gets cleaned weekly, and the main sponges next to never.

I could re-phrase my question slightly to see if it helps bring it to life:

Q: If you had three trays to fill in a canister and wanted to maximise surface area, would you fill all three with HELX-13/K1 (3 x 800ml) or fill all three with 20PPI/30PPI foam?

 

[fredi]

Me I would use 30ppi foam, because that’s what I do 😂😂👍

 

[dw1305]

Hi all,

But still interested in how to compare K1/HEL-X surface area when compared to the same volume (20PPI or 30PPI) of foam! It's frying my noodle!

The <"Aquarium Science website"> has some figures.

I <"also know"> that <"Viktor Jarikov"> was / is a sponge user. Therefore I'm going to say <"it doesn't make much difference">.

There is actually an "easy way" to tell what works, and that is to look at aquaculture, and in that case <"fluidised Floating Cell Media"> (like Kaldnes K1 and Hel-X) is the weapon of choice, using a <"Moving bed biofilm reactor - Wikipedia">. I know that @Wookii is a <"fan as well">.

The Oase does have a 45PPI pre-filter that 'protects' the media in the main unit. The pre-filter gets cleaned weekly,

However unless fine media is present, particles will flow through the filter, if fine media is present, it will block relatively quickly

I'm going to say that is the important bit.

cheers Darrel

 

[fredi]

Hi all,

The <"Aquarium Science website"> has some figures.

I <"also know"> that <"Viktor Jarikov"> was / is a sponge user. Therefore I'm going to say <"it doesn't make much difference">.

There is actually an "easy way" to tell what works, and that is to look at aquaculture, and in that case <"fluidised Floating Cell Media"> (like Kaldnes K1 and Hel-X) is the weapon of choice, using a <"Moving bed biofilm reactor - Wikipedia">. I know that @Wookii is a <"fan as well">.


I'm going to say that is the important bit.

cheers Darrel

Eheim pre filters are around 10ppi (not measured one, but it looks around 10ppi to me)

 

[dw1305]

Hi all,

Eheim pre filters are around 10ppi (not measured one, but it looks around 10ppi to me)

They are 10, or 15, ppi sponge. I've got a few of them, but none in use at the moment. For preference I'm using the <"big sponge blocks"> on filter intakes (as well as powerheads), partially because you can get away with <"cleaning them less frequently">.

cheers Darrel

 

[Wookii]

I am not sure that the 2 media are “equivalent” in effectiveness, in terms of surface area
If the k1 is kept mobile, it will require less cleaning
However unless fine media is present, particles will flow through the filter, if fine media is present, it will block relatively quickly

+1 to the above - though both types can act as biological media, they have a very different function. Foam provides effective mechanical filtration but will clog over time, floating plastic media is largely self cleaning for the most part and provide more effective microbial surfaces because of that constant renewal.

Regarding the OP question though, I don't think surface area is a particularly useful metric to be honest because a) surface area really isn't that useful when comparing similar media, and b) it is a static measure of something used in a dynamic system - there are far far too many more important variables that alter the effectiveness of biological filtration, long before the surface area of media ever needs to be a consideration.

There is actually an "easy way" to tell what works, and that is to look at aquaculture, and in that case <"fluidised Floating Cell Media"> (like Kaldnes K1 and Hel-X) is the weapon of choice, using a <"Moving bed biofilm reactor - Wikipedia">. I know that @Wookii is a <"fan as well">.

I am, a big fan - for my money, a decent mechanical pre-filter combined with plastic floating biological media, and its job done. I use the Oase Hel-X media in all my filters, including about 8 litres of the stuff in the wet/dry trickle filter on my sump tank.

 

[dw1305]

Hi all,

a decent mechanical pre-filter combined with plastic floating biological media, and its job done

As you say "job done" <"https://www.sciencedirect.com/science/article/pii/S0144860905000531"> - "Bjorn Rusten, Bjørnar Eikebrokk, Yngve Ulgenes, Eivind Lygren, (2006) "Design and operations of the Kaldnes moving bed biofilm reactors",
Aquacultural Engineering, 34:3, pp. 322-331," and an updated review paper: <"https://www.sciencedirect.com/science/article/pii/S2468550X21000587"> Shitu, A. et al. (2022) "Recent advances in application of moving bed bioreactors for wastewater treatment from recirculating aquaculture systems: A review" Aquaculture and Fisheries" 7:3, pp. 244-258.

Regarding the OP question though, I don't think surface area is a particularly useful metric to be honest because a) surface area really isn't that useful when comparing similar media, and b) it is a static measure of something used in a dynamic system - there are far far too many more important variables that alter the effectiveness of biological filtration, long before the surface area of media ever needs to be a consideration.

Same for me.

cheers Darrel

 

[Bradders]

Foam provides effective mechanical filtration but will clog over time

If you don't clean your foam very often, I am assuming that it does provide bio-filtration. Would you concur?

 

[Wookii]

If you don't clean your foam very often, I am assuming that it does provide bio-filtration. Would you concur?

Yep, thats why I said:

both types can act as biological media

I was just pointing out that foam also provides mechanical filtration where floating media doesn't.

 

[Bradders]

Yep, thats why I said:

Sorry, I need to read slower and more precisely!

 

[dw1305]

Hi all,

If you don't clean your foam very often, I am assuming that it does provide bio-filtration

Exactly that, any "mechanical filtration" media is going to <"start to become biological filtration media"> as soon as it is wet.

cheers Darrel

 

[Wookii]

Sorry, I need to read slower and more precisely!

No worries at all.

If you don't clean your foam very often

Also worth pointing out that washing the sponge doesn't necessarily negate its ability to provide biological filtration - indeed the opposite can even be true. Areas of sponge clogged with detritus may have lower levels of DO, which will reduce the biological filtration capacity. Good flow of dissolved oxygen through the filter is the key.

As I found out from advice on this forum (probably from Darrel lol) even washing under the tap is fine - the levels of chlorine in our tap water are likely not high enough to cause significant damage to the microbial population on a filter sponge, even when its washed under the tap.

Indeed, my other past time - brewing, I've learnt that tap water contains a decent amount of bacteria itself despite the inclusion of chlorine. For example you can't use equipment that has been cleaned but finally rinsed in tap water, as it risks the introduction of infections into pre-fermented wort, and fermented beer - all equipment and vessels have to have a final rinse in food safe sanitizer immediately prior to use to kill all microorganisms.

 

[Bradders]

I am, a big fan - for my money, a decent mechanical pre-filter combined with plastic floating biological media, and its job done. I use the Oase Hel-X media in all my filters, including about 8 litres of the stuff in the wet/dry trickle filter on my sump tank.

Oase came back to me on another question, and they said that HEL-X13 will break down around 6.5g of food per day per litre. So your 8 litres should handle 52g of food breakdown per day.

Now, if we do some basic (and estimative) math and assume that you feed around 1% of metabolic fish weight, it should handle around 5.2 kg of fish!!

 

[Bradders]

As I found out from advice on this forum (probably from Darrel lol) even washing under the tap is fine

Yes, my researching also led me to that fact. However, it did seem to come with a caveat that the filter needs to be mature. i.e. washing every week will remove more microbial population and create a start again effect, rather than washing after 6 months +. It seems to hang on for dear life more the older it is!

 

[Wookii]

Oase came back to me on another question, and they said that HEL-X13 will break down around 6.5g of food per day per litre. So your 8 litres should handle 52g of food breakdown per day.

Now, if we do some basic (and estimative) math and assume that you feed around 1% of metabolic fish weight, it should handle around 5.2 kg of fish!!

lol that from Oase sounds dubious advice at best! As I mentioned above, there are far too many other variables. For example, my filter is a wet/dry trickle filter, so all filter media is exposed to 21% concentration of atmospheric levels of oxygen - that's about 210,000ppm, vs 8ppm of DO saturated water - making them significantly more efficient.

Whilst this is all interesting academic stuff, providing the filter is appropriate for the tank size, the decision on how many, or what type of fish, to stock is however completely unrelated to the filter and certainly to the type of filter media used in that filter. I do love a car analogy, to basing stocking capacity on the quantity of filter media used would akin choosing the safe speed you should drive at based on nothing but the aerodynamics of your car!

 

[Wookii]

I should also add, for a good quality stocking calculator/planner, this is one of the best I've used:

https://aqadvisor.com/

Though in all cases, all tanks are different, and need to be considered in context of things such as tank layout vs species selected etc.