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andycook
10/07/2013, 10:48 PM
After many years in and out of this hobby I have come to the realization that I have always given too little attention to mechanical filtration. In years past I ran a sand bed and even a deep sand bed. That allowed me the (temporary) luxury of following the "out of sight out of mind" philosophy of mechanical filtration. No tank stayed running long enough (upgrade, change in equipment, moving) for this to become a real problem.

Now with the bare bottom tank I have now I realize that I have a lot of gunk to get out of the tank. The flow in the tank does a pretty good job of keeping the gunk I stir up suspended in the water column and even into the sump. The sump is a settling zone. There is still a lot of gunk in the tank.

I tried filter socks. Those seem to be fine for the day when it is business as usual but they clog pretty darn fast especially after stirring up the tank.

I suppose I could wait until the two snails I have finally clean all the rock and the glass and the boat board. If only the snails worked in a more consistent left to right pattern :)

I may run a couple of cannister filters until I get ahead of the mess.

There seems to be less mention of mechanical filtration than I would expect when I do a search here.

Perhaps this is my freshwater planted tank influence - I always let the gunk go into the substrate for the plant.

BrianB421
10/08/2013, 02:56 AM
Mechanical filtration is important but not always needed. I personally only run filter socks the day or two following a water change to remove anything I may have stirred up. I also have an oversized skimmer that makes up for it. I think most people view mechanical filtration as more time consuming work so it gets a bad rap.

Craigdillman
10/08/2013, 10:07 AM
I'm really debating changing my sump as well before my new system goes wet, I have filter socks but I'm thinking maybe a over under mechanical filter section

foxsavage
10/08/2013, 10:16 AM
I run a diatom filter a couple times a year and I stir the tank up real good and blow off all the rocks with a powerhead while it's running. It does a great job.

andycook
10/08/2013, 06:30 PM
So you let the detritus rot and then get skimmed out? I think I want it out sooner than that.

I have to switch to something more aggressive than one snail, filter socks sometimes, and a small settling section in my sump. Once the tank is clean(er) I'm sure I can drop back to just socks around cleaning time.

Mechanical filtration is important but not always needed. I personally only run filter socks the day or two following a water change to remove anything I may have stirred up. I also have an oversized skimmer that makes up for it. I think most people view mechanical filtration as more time consuming work so it gets a bad rap.

BrianB421
10/09/2013, 12:39 AM
I don't argue the beneifts of running a filter sock. I just don't need to run it all the time to keep my levels in check. For me, the juice isn't worth the squeeze.

Ron Reefman
10/09/2013, 06:02 AM
You want to clean things up in your tank, and then you complain when the filter socks need to be changed because they are cleaning up your tank. You want something to clean your tank for you that you don't have to tend to. Good luck with that.

andycook
10/09/2013, 06:37 AM
BrianB421 - I wish I were at the point where I could run filter socks once in a while. I'm stepping up the mechanical filtration right now with a HOB filter with hopes of getting to the point where I can allow the detritus to rot and have the skimmer handle it or use the filter socks as needed. I think I made a mistate over the years of not having much if any mechanical filtration. I'm wondering if I should have a HOB on my system at all times. I guess I have to do so for a year or more and see if I can conclude that the mechanical filtration had any long term benefit vs the effort/maintenance.

Ron Reefman - I am not sure how your response applies here but thanks for participating.

Reeferz412
10/09/2013, 06:46 AM
I run my HOB filter as my means of mechanical filtration. I let hair algae grow in my filter and the scrubber I designed to frame the output of the aquaclear filter. I never clean that filter out and I know there is a crud ton of detritus probably on the bottom of it. I run an eshopps skimmer for any broken down organics. I was thinking of adding a sponge and routinely cleaning it, but I am on that same boat... not really looking forward to pulling it out and cleaning it every 2-3 weeks.. plus I really don't need it.

BrianB421
10/09/2013, 07:40 AM
BrianB421 - I wish I were at the point where I could run filter socks once in a while. I'm stepping up the mechanical filtration right now with a HOB filter with hopes of getting to the point where I can allow the detritus to rot and have the skimmer handle it or use the filter socks as needed. I think I made a mistate over the years of not having much if any mechanical filtration. I'm wondering if I should have a HOB on my system at all times. I guess I have to do so for a year or more and see if I can conclude that the mechanical filtration had any long term benefit vs the effort/maintenance.

Ron Reefman - I am not sure how your response applies here but thanks for participating.

andycook - Like so many things in this hobby, there are a plethera of variables at play that allow some tactics to bring success to one tank and destruction to another. That's why there is no "one right way" to have a successful tank.

But as the saying goes, "Opinions are like @$$ holes. Everybody has one, but mine is clearly the most awesome." So here we go...

You mentioned "letting detritus rot" a few times. A skimmer doesn't wait until detritus has broken down into the ammonia cycle before it removes the waste. Quite the opposite actually. It's removing the waste that is still floating around the water column that has yet to fully decay. The skimmer creates foam that pushes this waste up into the cup, separating it completely from the water. That is why the skimmer is debatably a means of mechanical filtration. IMO, one of the keys to having your skimmer be as impactful to your tank as it can be is good water flow in your tank. Chaotic and strong flow keeps the detritus in the water column and keeps it from collecting in dead zones and rotting in the tank. The pro to the skimmer is that the waste is completely removed from the tank and will not add to the nutrients in your tank. A filter sock will trap large bits of detritus in a high flow, high oxygen environment. This drastically speeds up rate of decay and adds nutrients right back to your tank. This can be mitigated by consistently removing and washing the socks. Plus, most filter socks only catch really large bits of crud. If you have good flow in your main display, the larger pieces will be broken up long before it hits the sock. This is why I don't like using a filter sock to keep nutrients down.

As I said before, I will use a filter sock after I stir up the tank with a water change. But I think most of what's getting removed is silt and other water clouding nasties.

Plus, I've got feather dusters all over my live rock and I figure they enjoy the extra floties I'm leaving them...

BrianB421
10/09/2013, 07:43 AM
I was thinking of adding a sponge and routinely cleaning it, but I am on that same boat... not really looking forward to pulling it out and cleaning it every 2-3 weeks.. plus I really don't need it.

In 2-3 weeks, any sponge/filter will be a fully functioning nitrate factory. To have all the good effects and less of the negative, you'd need to change that filter out at least every 2-3 days.

KafudaFish
10/09/2013, 08:07 AM
Of course stocking is important but another factor to consider is the size of the aquarium. The smaller the system, the more important MF becomes for long term success.

You mentioned time frame due to life and with small nano to pico-sized tanks often being upgraded etc. or just being broken down due to issues (which seems like clockwork in this area), to me one of the overlooked areas is physical removal of waste.


Even with 100% WC/month and no sand bed the amount of detritus that accumulates is staggering.

ca1ore
10/09/2013, 08:34 AM
There have been many threads here on RC debating, and arguing :), the merits of filter socks. I don't think anyone would argue that the removal of settling detritus is a good thing, and better sooner than later, but the actual mechanism always raises passions. Personally I do not use filter socks continuously. I'm just not very good at regularly cleaning them, so the idea of forcing water through a detritus-laden sock just doesn't seem like a good one to me. I do employ as sock when I am doing maintenance in the tank that is likely to kick up stuff, but only until any suspended detritus has cleared. I think if you are able to switch out socks regularly, say every couple of days, that they are worthwhile. My own personal preference is to employ very high flow in the display and then a settling chamber in my sump that can be drained as needed.

Reeferz412
10/09/2013, 09:07 AM
In 2-3 weeks, any sponge/filter will be a fully functioning nitrate factory. To have all the good effects and less of the negative, you'd need to change that filter out at least every 2-3 days.

"Nitrate factory" gotta love that rarely used term. I have never cleaned that filter out. Plus I use the negative (being hair algae) for good. DT looks great and no hair algae in the DT. Hence why I don't use a sponge that came with the Aquaclear.

BrianB421
10/09/2013, 10:10 AM
^^^ You know it! haha

dax123
10/09/2013, 10:33 AM
Here is an option if you have a HOB or canister filter lying around. When you do your maintenance, stuff the HOB or canister with floss (cheap as hell) and put it on the tank. Stir up the gunk and let the floss trap it all. Leave the filter running for a couple of hours after you're done and then remove it from the tank. Discard the floss and that's it. You might want to turn off your sump return while doing this.

andycook
10/09/2013, 07:09 PM
Bingo! Exactly what I am doing now. The filter floss arrived in the mail on Monday. Now I stir a detritus tornado and let the HOB do the work.

Here is an option if you have a HOB or canister filter lying around. When you do your maintenance, stuff the HOB or canister with floss (cheap as hell) and put it on the tank. Stir up the gunk and let the floss trap it all. Leave the filter running for a couple of hours after you're done and then remove it from the tank. Discard the floss and that's it. You might want to turn off your sump return while doing this.