HMF-style mechanical filtration in sump?

[David R]

The poret comes in 50x50cm sheets and the sump will be 48cm wide internally, so there will be a bit of squeeze on the sheets. The local Poret guy thinks that will be enough to keep the sheets in place, but I was going to get the tank maker to put a couple of small pieces of glass up the sides (and maybe one in the centre) to hold the foam in place.

If I could come up with some sort of effective pre-filter for the socks I would use them in a heartbeat, they're certainly the best mechanical filtration I've used before. But because of the large quantity of physical waste from the Panaques I think even with four of them they will need changing too often. I know the settling chamber will work and will really reduce the amount of physical crap that gets to the sponges.

 

[Gill Blue]

I have a 4"x4" block of 20ppi, 4" sheet of 30 ppi, and 2" of 45 ppi poret. and it's not fine enough to keep the water any better than hazy.
I'm actually running an emperor 400 in the sump with polyfill and felt for fine particulate removal.I run it in the pump section after all the bio.

45ppi vs. 100 micron image
as you can see from the pic in that post, 45 ppi isn't all that fine.

you want a bit of a squeeze with the foam, mine is pretty snug, but I still needed to top it off with eggcrate and 2 rocks to keep it from rising with the water, as well as some pvc underneath to keep the rocks from pushing it to the bottom.

 

[David R]

Interesting, good to hear some real-life experience using this stuff. I understand the foam has considerably larger "holes" than something like a 100 or 50 micron filter sock, but I gather that over time as they accumulate gunk that increases the ability of the foam to catch finer particles. Looking at your sump though it does seem like a fair bit of stuff will make it through, even with the 45ppi foam. Its as though I need to incorporate the socks after the foam some how, at this rate I'm going to end up with a sump that is longer than my tank!!

Something in that link to your thread caught my eye;

Now if I could DIY-up something like that to catch the coarse waste before the filter socks I think it could be very effective in removing the large physical waste! Time to do more research, no doubt there will be a new thread soon with more crappy mspaint drawings....

 

[Miguel]

I never had a problem with keeping the foam in place between the glass plates.

As said, i put a small cover of glass wool ( looks like cotton ) on top of the foam to avoid coarse and less coarse material to clogg the foam.

One thing i do not understand with that decanter chamber you mention. The materail stays there, but you need to remove it. Is it not easier to clean sockets?

 

[Rayne]

I always considered Poret as more of a biological filter than a mechanical one. Sure it can do mechanical too but in my opinion its real strength lies in the biological since denitrification can take place in the thicker pieces of foam.

Here is an interesting read from the owner of Swiss Tropicals - https://docs.google.com/file/d/0B71CK9SG9ShCZEhOZ0xOVUlyNXM/edit?usp=sharing

PS - What about implementing filter socks after your settling chamber? That way most of the heavy mulm will settle out and not clog up your socks as quick, but you could still implement some finer mech filtration. Also, then your Poret wont require cleaning as often too, which would be harder than spraying out a filter sock or two.

 

[Gill Blue]

this may help. http://www.amazon.com/s/ref=nb_sb_n...eld-keywords=fine+sieve&rh=i:aps,k:fine+sieve

 

[David R]

One thing i do not understand with that decanter chamber you mention. The materail stays there, but you need to remove it. Is it not easier to clean sockets?

Not really! The settling chamber will need to be siphoned during water changes but that is about on-par with rinsing and washing socks in terms of work, the big difference is the frequency and urgency of doing that work. The thing with the settling chamber is that it can't/won't clog, you could leave it for a year and the only think that would happen is so much poo accumulates it overflows into the next chamber (although by then the quantity of waste would be making the water pretty nasty). If you leave the socks too long they overflow and you basically lose your mechanical filtration and the crap ends up in your bio media.

Rayne, my problem with having the settling chamber then socks is I'm limited to about 900mm total height, so with 100mm for a base, 300mm water level, 3-400mm for the socks above the water level, and 50mm for a diverter to catch the water coming from the chamber and put it into the socks I'm starting to run out of height. I guess if I could somehow build it into one tank as-per the above HMF-idea (rather than having a separate settling chamber and sump as I did with my 800L tank it could possibly work, I'll do some drawing and see what I can work out.

The more I think about it, the more I like the idea of a Cetus Sieve type screen pre-filter as it removes the waste from the water column rather than leaving it there to break down like the settling chamber does.

 

[Miguel]

Pray show us what that cetus sieve is?

 

[David R]

There's a pic of one about five posts up.
http://youtu.be/0noGwwycu8Q