Advice for DIY K1 moving bed filter

[Giant Val]

Hi everyone,
I bought two 30L (9 gal) drums to use as K1 moving bed filters. I have a question about the best way to go about it. Could I plumb them to the outlet of a FX6, or should I plumb them directly to an inlet and outlet in the tank. If they should be plumbed directly to the tank, what sort of pump should I use and where should it be located? I intend to agitate the K1 using an airstone in each drum. Any help would be appreciated.

 

[aotechs]

Using an FX6 as your only return, the simplest idea I have, would be locating the containers above the tank. This would allow gravity to return the water from the K1 filter to tank.

Flow route: Aquarium -> FX6 -> K1 -> Aquarium

If the containers are filled to 60% volume with K1, they will only hold 18L of media. What size of tank are you planning to filter?

 

[Giant Val]

Thanks for the reply. Tank is 8x3x2 (315 gal) and already has three FX6 filters, so the drums would be for supplementary nitrification. Tank has been up and running for about 2 years now. Agree having the drums after a FX6 would be simplest, but drums above the tank to gravity feed into tank isn't possible with my setup. I was hoping to have the drums after a FX6 as you describe, but underneath the tank. Would the FX6 motor be okay to push the water through the drum then back up to tank?

 

[takagari]

you need a prefilter with k1, so if you go with a separate setup be sure to prefilter

 

[Giant Val]

OK, thanks for that info. That makes sense, so I think I'll run them after a FX6. Can anyone think any reason why that won't work? Also could I put the two drums in line after a single FX6, or should they be after separate FX6s?

 

[BMac91]

OK, thanks for that info. That makes sense, so I think I'll run them after a FX6. Can anyone think any reason why that won't work? Also could I put the two drums in line after a single FX6, or should they be after separate FX6s?

I may be completely incorrect here, but I see no reason why that WOULD work. All your pressurized water from the FX6 is getting pumped into additional containers, so you'd need another pump that was taking the water from the k1 containers and sending it back up to the tank.
If it was me, I'd leave them on their own and do a pump afterwards. Thats just me though.

 

[jwh]

Also can't see this work. The drums have to be open open to allow for airstone agitation. If you pump the return from a fx6 into the drum it will simply overflow. You'll need to add a pump that has exactly the same out put as the fx6 to keep things balanced, for that you'll probably need an adjustable dc motor. I may not get it, but I see flooding.

 

[Giant Val]

Thanks for the feedback. The lid would be on and water tight. I'm planning to put the airhose through hole drilled in the side of the drum and make watertight with silicone. Also planning to put an air-bleed valve on the top so the air can escape from the drum. Perhaps an alternative to the aerator is a wavemaker to agitate the K1. The cable would go through drill hole, siliconed to make watertight.

I'm assuming if its watertight, then the FX6 pump would return the water to the tank, with perhaps a little less flow rate due to additional friction loss. But I might be wrong.

 

[Jez1992]

I'm sorry but I agree with the above.i can't see how this will work. The idea of k1is so it fluidises.

By putting them in line they will be pressurised and therefore be stagnant mostly. It will also be a massive pain for you to clean etc.

You would be better suited is they are going in line to just fill them will submerged media that has more surface area.

Whilst your on the top is of filtration, for a tank that size have you thought about changing to a sump. Would be a better filter and use less power than three of those fluvals?

 

[Giant Val]

Thanks for the advice everyone. I wish I could install a sump, but the cabinet only has small doors and I can't fit anything bigger than a two foot tank underneath. That's why I went for the FX6s. Perhaps I'll forget the K1 and put in some solid high surface area medium as you suggest. Thanks again everyone. This is a great forum with plenty of people willing to chip and share their experience.