Fluval FX6 Aquarium Canister Filter in Hydroponics

I decided to post this because almost nowhere can you find filtration discussions or guides. Like most i started without filtration and was challenged by constant maintenance to keep things healthy and clean. Airstones are your canary in the coal mine so to speak, and what took me down this path was trying to find a way to maintain these in late flower when you cant exactly move plants to easily. In short, this thing is amazing, after i set this up i have 0 partices in the nute solution, any floating algae, or anything bigger tham 20 microns is filtered out at 900 gph through this filter. I actually ran the same res for 6 weeks from seedling to flower and not only was it still clean, but the airstones were spotless, coupled with treating the res with Dr. Tims Aquatics Waste Away bacteria for aquariums that actually eats root rot. Anyway, for those that care to have a look.


What are you running in your canister? The original bio rocks and carbon with the filter pads or have you mixed it up?

@BigItch the bottom black pad is carbon filter infused, i removed that. Then used the same biofilter media in the center and moved the red trays around so i have the 2 outside are the black lumpy filter, then some of below, bio filter in center, more of below, then another black lumpy filter. The sides i kept the same.


Hey im pretty sure the carbon in ur filter will take out the nutrients out of ur water in ur res cause i know it takes out chlorine and it also helps with ammonia but im sure it may take out ur nutes specially ur micro nutrients lile iron and that just keep i good eye on it but i so love the use of a canister filter i used to use these with my fish breeding over the years but i maybe wrong but it’s something to watch out for

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I agree with this. But I don’t do hydro.

Great job , :clap: i love it , it can and will work as long as you filtering the water not your feeding nutrient water , so if you recirculating your runoff yes perfect , but you must stabilize the water before feeding .

@Aussie_autos your 100% correct. This has been removed, and replaced with the other media in the pictures. There is only mechanical filters, and bio for beneficial bacteria.

Sweet i love ur idea to use the filter it would keep the water a lot more clean and healthy for ur plants and there much quieter than a normal pond pump


@yoshi Actually this is filtering the entire volume of nutrient solution recirculating through the RDWC. Its stand alone and the recirculation pump is a 2000 gph pond pump the filter is 1k and constantly cycles the 55 gal res. I actually questioned this myself big time, but everywhere i looked basically said the same thing. If your nutrients are water soluble then you need either carbon, ammonia, specialty filter media, or reverse osmosis to remove them. Did you see, or expirence anything different im super curious because i havent seen anyone do this, but read it was a good idea from some non canabis hydroponics science type sites.