Nerd alert! Question what is are the benefits/costs of pours per inch in Matten filters?

[Tedrock]

Howdy Nerms, 

This is a total fish nerd question (but an important one as I am about ready to buy another set of Matten filters).  I am trying to decide on pours per inch cost analysis.  I don’t know if it is really a 10 per inch but it is a ratio of increments based on inch.  So with that being said, is there advantages for 10 over 30 ppi in water flow verse filtering bacteria power/area?  It appears that a higher ppi rating would become clogged sooner.  Can others offer insights into this area or am I just over thinking it?

Many thanks,

Tedrock

[TOtrees]

I think the ppi is low enough in this case, just based on the pic. Fine sponge does require cleaning more often, or the performance degrades. Yes, the fine sponge polishes the water a bit better, but I'll take that trade off in my tanks every day. The coarser sponges are great (though sadly i think the ACO sponge is too coarse). 

[Tedrock]

Why do you think the A-coop sponge is so coarse?  What is the benefits?

[TOtrees]

@Tedrock are you asking why it's as coarse as it is, or why I think it's too coarse? 

For the first question, all design choices go back to Cory. He chose the coarseness of the foam. Based on his various descriptions and comments on various streams and vids, I'd say it's performance and maintenance. More open foam means more flow through the sponge, so better circulation throughout the tank. It also means less debris is trapped, which means less maintenance. I have a couple of ACO sponges running, and they need rinsing far less often than others (eg Hydro Pro). When they are rinsed, they are holding less poop/debris. So you can probably go half a year or more without having to remove and rinse the filters. If you run a hundred tanks, that's a significant consideration. And you're less likely to run into circulation problems if maintenance is overdue. 

For the second question (why my opinion), I just think that the overly large pore size lets too much physical debris through. For me. And my preferences. I want the filter to trap debris, which I'll remove periodically. I also think the inner core/chamber of the sponge filters is a bit too narrow, and combined with the large pore size this allows some  air bubbles escape out the top of the sponge, as opposed to going up the tube. If air is escaping this way, it's not traveling up the tube, and that means less water is being pulled through the sponge itself. Any part of the sponge that doesn't have optimal flow through it is simply passive surface area. Might as well be substrate or plant surfaces. This varies a bit with the setup (eg size of airstone, size of bubbles, rate of bubbles, etc). I acknowledge I might be splitting hairs and in a real world sense it might only be the difference between 100% vs 95% efficiency, and if that 5% makes or breaks your tank's health of safety you are flirting with disaster regardless of what sponge you like. Anyways, my 2c. 

[Odd Duck]

I’m with @TOtrees, think 10 pores per inch is extremely coarse for matten.  I’ve been using 30 in the mattens I use as substrate but I’m planning on trying some 20 ppi next.  30 has much more surface area for beneficial bacteria to colonize, but definitely has a higher risk of clogging.  I’ve used 20 ppi as packing for HOB filters and it just doesn’t clog even in my dirtiest tanks but I also have prefilters on all of my HOB’s.  Most of the prefilters are ACO’s that are probably about 10 ppi or maybe even slightly less.  Does their website say?  I can’t remember.  Finer prefilters definitely clog too fast and my dirtiest tanks can even clog an ACO prefilter.

I think 10 ppi in the prefilters and sponge filters works great but it definitely won’t polish your water.

[nabokovfan87]

On 9/14/2023 at 12:41 PM, Tedrock said:

Why do you think the A-coop sponge is so coarse?  What is the benefits?

It's preference.  Cory designed his sponge to run for a longer time and it does come at a cost (lower mechanical filtration capability)

That being said, there is a variety of foams available and there's a lot of different options out there for what "works well" based on application.

For a matten style filter, I think one major concern is the density of the foam and it's ability to trap, i.e. lock in, the debris.  It's a slower flow style filtration and the ability for that foam to trap debris is important. It takes effort to remove it and you're going to compress it/release some debris when you do so. 

You can look at the structure of the foam itself, even in the co-op sponge vs. other sponges.  There's open-cell, closed cell, but the main thing you'll see in difference is the structure.  Something like a matalla mat is similar structure to what you see in the co-op sponge filter, while the one above, hikari, and other brand sponges are more similar to something like "memory foam" style of sponge.  (structure of course, not elasticity)



Here's some side by side comparisons.

20ppi vs. 25ppi vs 30ppi (in order)

The last photo is a bit distant, but as the PPI goes up, you see it's "finer".  The particles that flow through are smaller and it's a bit harder for things to get stuck internally.  Meaning, it might be easier to clean.  What this means is that if you have a 15-25ppi sponge compared to something like 45-55ppi, it takes more pressure to remove the debris from the finer sponge, BUT it also is harder for that stuff to get deeper into the sponge.  Something to think about.

Visually, here's a cool example.  How do things "flow through" the structure, this is what you want to keep in mind.  In terms of baby fish, shrimp, snails, plant debris, algae, food particles, and actual waste, what is the best thing for your situation?  What is the application like?  Using a sponge in an air powered filter is much different than using foam in a canister filter.  It's night and day.  One of those is purely setup for mechanical filtration, as opposed to the other being primarily biological with some mechanical ability.

It's like everything else for me, how the sponge feels (if it's "crunchy" or if it's easy to clean), it's very difficult to tell without time in my hands and using it to really know.  Find a foam you like to work with, go from there.  After you use it for a year, if it isn't destroyed, quality stuff and I would recommend it.

On 9/15/2023 at 1:44 PM, Odd Duck said:

I think 10 ppi in the prefilters and sponge filters works great but it definitely won’t polish your water.

It also may not stop some pretty big debris from getting into the pump impeller.

[JChristophersAdventures]

@nabokovfan87 I am mainly interested in the ACO large intake pre-filter sponges. I know they are really coarse, but over-all I like that, but might slip a mesh "sock" over the intake before putting the sponge over that (let the sponge catch the big stuff and the mesh catch a lot of what gets through that). Is the ACO sponge flexible enough to be easily cleaned? Interested to know if you have another pre-filter sponge you like better I can check into. Thanks.

[nabokovfan87]

On 9/15/2023 at 5:13 PM, JChristophersAdventures said:

Is the ACO sponge flexible enough to be easily cleaned? Interested to know if you have another pre-filter sponge you like better I can check into.

I just got one in the mail today so I wasn't using the coarse one anymore.  I prefer the marineland ones.

I have one of the co-op nano prefilters that I think is a little bit finer than the big sponges.  I have a lot of issues with hole size vs. sponge size.  The nice thing about the ML ones is that they will always be one size, the hole is just a different size. two size holes, very easy to use.  Fluval also has nice nano ones.  Clean them often enough (once a week or so) and it's not a big deal of them choking or clogging.  Some people clean weekly, others monthly, some people never.

[gardenman]

A higher PPI filter could clog faster, but also provides more surface area for bacteria to grow. By and large, clogging isn't an issue with Matten filters. Matten filters are largely self-cleaning as nearly all of the waste that enters them is organic and organic stuff decomposes. Most Matten filters have a relatively slow flow rate so as one section clogs, water flows more through the less clogged areas. And while the water flows around the clogged section, the organic material that's clogging the flow is breaking down and decomposing, clearing the clog. There are stories out there (mostly from Europe where Matten filters have been used longer) of Matten filters going uncleaned for ten years or more and still working fine.

Clogging is more of an issue if you have a high flow rate through your Matten filter. You don't need a high flow rate through a Matten filter for it to be effective. I've seen heavily stocked tanks where the flow through the Matten filter is counted in drops per minute rather than gallons per hour.