Author Options:

Ca huge drinking water filtration system be modified for a fish tank? Answered

I got a few of these filtration units:
For drinking usage far too big but I was wondering if it would be possible to modify parts of it for filtering the water in my aquarium.
Inside the black canisters is a prefilter (big one) and a de-scaler cartridge (small one).
As they are independent from the quad filter system it only leaves the question of modifying some pipe for the inserts and finding a suitable filter medium.
Would be nice as a pre-filter to keep the worst crap out of the filter pump.


The forums are retiring in 2021 and are now closed for new topics and comments.
Jack A Lopez
Jack A Lopez

1 year ago

I see the words, "a few of these filtration units" and a colon, ":"

But I do not see a picture attached to this topic.

From what you have posted in the past, I gather you already know a lot about what your fish want, or don't want, in their water.

I am guessing the enclosures not pictured are made out of plastic, of some kind, or else you would not be considering them for use for filtering water for fish.

That is really the only I know about water chemistry for fish, is there are warnings about fish being sensitive to various dissolved metal ions,


and as a consequence of this, the fish hobbyist never uses metal pipes(e.g. copper, brass, iron, stainless steel, etc), or metal pipe fittings, for the plumbing for his or her fish. It is always plastic pipe and fittings, of some kind.

Also it is usually transition metals, like the middle of periodic table, that are worrisome. Alkali and alkaline earth metal ions (columns 1 and 2), like Na+, K+, Mg++, Ca++, are totally fine, or maybe even have to be there, especially in the case of a salt water aquarium.

I guess I do not know why, this thing you found, would not work for fish water. At the same time, I do not know what hidden dangers are lurking in it, if any.

It makes me wonder: Are there any fish cheap enough to be used as sentinel species?


It would be sort of like, you put one or two sentinel fish in first, to see if the water is safe to live in, and if they die then this indicates something is wrong with the water.

You know, like the proverbial canary in a coal mine.


Reply 1 year ago

Picture is attached up there and I can see it....
Guess what I am really wondering is whether or not adding such a filter system would be beneficial in terms of service life and water quality.
It is quite a hassle to clean the filter pump, which is located inside a cabinet under the tank.
Even if I could just use the pre-filter from the system and mount it outside it would make a big difference for the time it takes the filter pump to block up too much.
Problem is the system is rated for about 380.000 gallons of water, with a pump good for 1000 liters per hour that makes about 60 days of usage until the filter should be changed.
And don't get me wrong but I am not planning on 400 bucks every two months for new filter cartridges, so custom ones would go in.
But of course, having the option to just pop in some dedicated filters to fight unwanted stuff, like medications in the water would be great too.

Jack A Lopez
Jack A Lopez

Reply 1 year ago

I see it now. I had to turn mah adblocker off. Then I looked at the source, to see where that image is coming from,


and looking at it via that link, I get a picture big enough to see.

I think those black filter housings, one on the left side, one on the right, can be opened and refilled with something...

Those four little grey cylinders in the center, are, I think, disposable, and not made to be taken apart.

I know there exist refillable filter cartridges, and I can point to a video of someone refilling one, here:

It is essentially an empty shell, that could be filled with anything granular.

Although I am not sure how many different sizes exist, or how to specify these, and match them to a particular filter housing. Although the spec might be as easy as diameter and height, since they are all cylinder shaped.

Also I am not sure what the sizes are, in particular, for the ones in your picture.

There may be some other, more crude way, to reuse found filter housings, without the matching, refillable, filter shell, but I am not totally picturing how that would work. It kind of seems to me like there should be some walls, or a central pipe, or something, to constrain the flow of water, so water flows, mostly, through the whole volume of filter media.