prefilters on draw tubes of filters...

[Magnum Man]

so, they make those slip on foam tips, for the draw tubes of various filters for me, these have been pretty pointless, at least from a filter point of view... I could see using them to keep from sucking up fry or small crustations, but ai found them too quick to plug up, and reduce flow ( too high a maintenance for a busy guy... anyway, how my mind works... I thought of using chunks of Japan Mat, on the inlets I have several odd size chunks left over after cutting them down, for use in some of my hang on back filters.... if you used a fine toothed metal hole saw, drilled 1/2 to 3/4 of the way through your chunk, you could bore a hole just smaller than your draw tube, and make a friction fit piece of Japan Mat, as a prefilter... I originally bought the foam caps, as I had an old filter that still works, that I couldn't find the end, so the tube was wide open... Japan Mat would allow beneficial bacteria to grow,, prefilter, for large solids, fry, or just sand from the bottom of the tank, that gets stirred up from water changes or fish that work the sand...

 

[Archerfish]

In the early days of keeping brackish water tanks, I discovered a clump of Java Moss on the intake of a small canister filter. It had all sorts of debris imbedded within. With a siphon tube next to it, I squeezed, the debris dislodged and was sucked out of the tank. Hum I thought, what if I leave it there? Turns out it was a good move. That clump grew considerably requiring now and then trimming but continued to prefilter the water. Anyway, just thought I would mention it. Sure do like your posts Magnum Man!

 

[gimme30]

For anything other than preventing fry/shrimp getting sucked up I hate pre-filters. Filtering the filter is just dumb to me and like you said they clog up so quickly you're constantly cleaning the stupid things. I find Japan mat to be kinda messy but if you could get it to stay on it'd be a much better option. It might still trap fry on a strong intake though.

 

[Magnum Man]

this kind of brings up " the need" for a prefilter...
I would suspect unless you have small fry, or fish that are bred to severely handicap their swimming ( super long fins, dumbo fins, etc. ), that most healthy fish are capable of avoiding the suction... that doesn't mean people don't find fish stuck to their filter intakes, but expect most of those were dead or dieing...

one thing I like about the new Tidal hang on back filter design, is you can adjust the strength of flow... my canister filter, doesn't have that feature, nor did the whisper filters I used to run

 

[TwoTankAmin]

I an thre reverse. All of my filter intakes have a prefilter on them. These das they are mostly Poret 10 ppi foam but some use the 20 ppi. The roll of my prefilters is to keep the larger solid wastes from going into the media inside the filter, I can detach and rinse the pr-filters very quickly. I use a brine shrimp net for the smaller prefilters.

I also use the ATI prefilters on some tanks where I want a much larger prefilter. I bet them our using a much bigger fine mesh net. But I tend to overstock some tanks and the prefilter actually reduces the maint. I need to do on the filter itself. I still have 2/3 canisters running and I only clean them twice a year. Pert of being able to do that is because they are prefiltered.

The enemy of any filter is media clogging and prefilters reduce that potential. The way filters work means if you suck in lager organic particles, they gradually reduce in size because the "disintegrate" this allows them to clog more places. This can kill off bacteria by denying it the nutrients they need to do their job and also works to reduce their numbers since all they need in the biofil must be delivered to them. This is why I like the Matten filters. There are so many potential paths through them that it can take years before they need to be cleaned,

The one downside of prefilters is that they should not be allowed to clog as that eventually results in a great reduction in the intake flow. So it is important to rinse them regularly, I do it weekly. There is nothing worse than discovering a pre-filter has collapses inward due to clogging.

The most labor intense part of prefiltering is that I make most of them and it takes me a good 5 minutes o make one. But on my more lightly stocked tanks, the prefilters mean I can clean the main media less often. Plus they also trap food particles on which the fish and shrimp feed.

As always, this is how I prefer to do things. I am basically lazy which means I do not want to do any work not needed, Prefilters, for me, serve that gaol. But for others this mught not be the case.

In the early years I used to buy the Aquaclear foam ffor the 110 (500 gph) and cut thet to the size needed and then I "rti=une it into a rounded shape.

 

[gimme30]

This is why I like the Matten filters. There are so many potential paths through them that it can take years before they need to be cleaned,

I don't think Japanese mat was around back when I ran Mattens but I bet it would work great for that application! The thing with the HMF, and sponge filters in general, is that they take up so much real estate. Even pre-filters on a hob. That's fine for a breeding or quarantine tank, not so much for the show tank in the living room. I mean, unless you like the tangled plastic mat look.

@Magnum Man are you going to try this with your Tidal? That seems like the best of both worlds...when the mat clogs up, just turn up the flow and put off cleaning even longer!

 

[Magnum Man]

the Tidal's are as easy to clean as a prefilter... and right now I have nothing in a tank I'm worried about sucking up... my shrimp and small live bearer breeding tanks, just run sponge filters... I honestly don't know why I thought of the concept ( sometimes my brain just does that ), as I have no current need to prefilter, and doing so was too much maintenance when I tried it before...

 

[Magnum Man]

I do have some least cray fish ( Cambarellus diminutus "blue" ) coming this week, they are smaller than typical dwarf crays... they are going into my "dump tank", a 65 gallon, with a big tidal on it... they are neocardia sized crays, so I'll be watching those, and may need a prefilter???
if that's the case, I'll probably use the Japan mat...

 

[TwoTankAmin]

Here is an early picture of my 50 gal high tech planted tank- pressurized CO2 and power compact lighting. It is filtered with an Eheim Peo II 2-26 canister through which I pushed the CO2. You can see the spaybar in the upper left, However, I ultimately moves it so that it was placed vertically in the right rear corner.

The intake has a big ATI prefilter in it. It is at the bottom of the rear left corner. It remained there fore tha almost 10 years during which I ran this tank. You cannot see the prefilter or even the intake.

After a rescape and moving the return to the right rear and having it set up vertically, you cannot even see the return. The big prefilter is still at the bottom of the left rear corner.

(edited for typos)

One of the benefits of decor is that it can be used to hide things. FYI, the heater on the tank was a Hydor inline and was not inside the tank.

I cannot imagine not having prefilters on all my intakes. I am a fan of black backgrounds. I often paint the back glass and often the sides as well with black paint. This made me move towards using black Poret foams for the intakes which makes it way less visible.

Here is a 29 gal with a pair of AC filters. Both uplift tunes have black prefilters.

 

[fishorama]

I use prefilters to keep leaves & big debris out of my Aqua Clear HOBs. But not always...In tanks with java moss, duckweed or BBA the prefilters get clogged fast & are harder to clean well. & sometimes I forget to stick them back on (oops). When scooping out duckweed I can never get it all of course, so I leave off the prefilter & have to clean the filters often to get it more under control.

I have mostly used AC filter sponges (20ppi) but also ATIs; a 10ppi doesn't clog as easily but doesn't trap as much debris either. When I had shrimp, I tried various fine mesh-type things to keep shrimplets out with a small low flow filter. Some shrimp keepers use stainless steel fine screen prefilters but I never tried those. I had many shrimplets but I'm not sure some didn't get into the filter to die there. At first I tried to rescue any I sucked out during water changes but that was very eye straining (is it a tiny shrimp or tiny poo?).

I don't think large pore prefilters will keep shrimplets or tiny crays safe. I'm not sure what size Japan mat might be but I'm doubtful...

 

[gimme30]

I use prefilters to keep leaves & big debris out of my Aqua Clear HOBs.

That's most people's reasoning for it but it doesn't make any sense to me. And I don't mean to single you out or cause offense-I realize I'm in the minority on this. Actually I might be the only one that feels this way. So feel free to poke me in the eye with your aquascaping tweezers should we ever meet.

I am all about low maintenance, which is partly why I'm down to just one tank. Well, ok, 4 actually, but I have no idea how that happened. A prefilter is one extra step I'd rather not deal with. Why not let the filter do what it's supposed to do? HOBs in particular are easy to clean and don't clog as quickly as the sponge will. Canisters aren't as easy but they're gonna gunk up eventually whether prefiltered or not, but that's what, a once or twice a year chore? I've never had a cycle crash due to a clogged filter...I'm sure it'd be a possibility if I ignored it until flow was reduced to a trickle but I'm not that lazy.

I guess I'm spoiled by the Best Filtration Method Ever. (tm) Cover your ears kiddies, parental advisory warning, here comes the foul language...UNDERGRAVEL FILTER. Yep, I said it. No muss no fuss no stupid sponges to clean as low maintenance as it gets! And far more effective than anything else. Plus they don't suck up your fry or shrimp.

Flame suit on, blast away!

 

[Uberhoust]

Since discovering pre-filters I have always used them. I initially started with foam based pre filters such as the pre made ones, but since then I have changed to using a very fine mesh substrate bag as my prefilter. I put it over the inlet using some pvc or abs tubing that has been drilled out around the outside to keep the functional surface area large enough to not interfere with the flow through the filter in general.

With the cloth mesh there is one aspect that foam cannot provide and it is trapping the majority of un-eaten food at the prefilter where the fish and snails can eat it. In most foam material much of the uneaten food ends up trapped in the pores that the fish cannot access, this causes a build up of materials in the prefilter eventually plugging the filter requiring cleaning, and or the food starts to breakdown in the prefilter causing degradation of the water quality.

By using a filtering cloth or membrane the food trapped is very visible to the fish keeper, so you know when you overfed. It will not provide any meaningful increase in the de-nitrifying bacteria, but it improves the main filter's ability to do this task by reducing uneaten food from entering the filter.

I have used this method on 75 gallon tank housing 9 angels for the last 3 years. I haven't had to clean the pre-filter yet, and only clean the main filter, fluval 407, only every 6 months.

 

[Uberhoust]

Example of the type of Prefilter I have been using, from a previous post.