Denitrate filter idea...

[MarkS]

I had an idea of a denitrification filter that I wanted some thoughts on.

Basically, what it would be is an acrylic box, 12" wide by 12" deep and 18" - 24" tall. The top would be removable for maintenance. Water would flow from the main tank into the filter either be a small powerhead or overflow. The water would then be pumped back to the tank or sump.

The filter media consists of nothing more than 12 inches of sand. It would also be a good idea to add detrivores as a prefilter would only trap the detrius and become a nitrate factory, defeating the purpose.

What is different about this from a fluidized bed filter it that the water is not forced through the sand. The water seeps down into the sand just like a sand bed in a tank and due to this, it provides a good and very large anaerobic area.

The return pump would be located either on the top or the side, but would be plumbed to the side above the sand. There would be no water pressure through the sand other than the pressure from the inlet.

The reason for this filter is that many people do not want a DSB in their tanks or do not want to go through the trouble of installing or cannot install a sump/refugium. Also, a great many people have CC beds and cannot or will not remove them due to the trouble involved. These people could still use this without much modification to their set up.

Any thoughts?

Mark

[Neal359]

i got a denitrator for about $40 and it work really well the way it work is its gravity feed into a tube that about 13in tall and about 3 in wide. when it enters the tub it goes through a VERY long black airline tube. this is were the anrobic bacteria live the water goes through it really slow. the black air line tub exits at the botem inside the denitratior the rest of it fills up and the water exits out a the top of it. it takes about 7-9 weeks to get it to start working but it brought my nitrates from 30ppm to around 5-10.

[MarkS]

Just bumpin' up ^^^^^^^

[Boatwizard]

I've been toying around with some denitrator ideas.
What about a small tank or plastic waste basket, filled with CC or sand, use a plate made out or acrylic on the bottom to spread the water evenly. Pump the water from botton to top using a very small pump. The overflow in the cotainer could be put in the side using a bulkhead, so only a lid would need to be placed over the top. It would need to be a couple of inches taller than the sump.

With a system without a sump, use a 3 or 4 inch diameter PVC pipe about 3 or 4 feet long. Pump the water in the bottom and flow to the top. Use sand or CC.

If you didn't want to drill a hole in the bottom, place your inlet hose in the top and run it through the media to the bottom.

Have you seen the PVC fencing for the yard? It's about 4 inches square and would make a great tower-type device.

HTH

[MarkS]

Water flowing down into the sand under it's own pressure will be depleated of oxygen by the time it reaches the lower depths where denitrification occurs. This is what you want and what my filter does.

What you decribed is a Fluidized Bed Filter. FBF's cause nitrates. They pump water through the sand either from the top or bottom and because of this, there is always oxygenated water coming in contact with all of the sand. This completely eliminates the anaerobic zones. So they convert nitrite to nitrate, but the process goes no further.

My design avoids this by allowing the water to flow down by it's own pressure. This means that the water at the bottom has almost no oxygen and denitrification will occur. The pump mearly pumps off water above the sand back into the tank. Water flows into the filter by gravity.

Also, you would want to use sand instead of CC because CC will trap detrius and end up causeing more nitrates to build up. It would be far better to have a 12" sand bed seeded with a detrivore kit.

Mark

[saltjunkie]

Im tring to follow you here mark, maybe im just blind? Can you sketch up something for me? You can email me if you dont want the whole world to see it. I am interested in seeing this?
Rick

[MarkS]

Sorry, it is a little crude, however I did this in about 5 minutes. I am currently working on the 3D model of this and will post it as soon as I am done.

Does it make sense now?

[saltjunkie]

ok, i got it, just a really really dsb with slow water flow, ty.

[MarkS]

It just sits outside of the tank. It would be useful for people who do not want a DSB in their tank and/or do not have room for a large sump to contain a DSB.

Mark

[RobG]

Very similar to a CPR hang-on refug? Except it doesn't hang-on... ;)

You have more surface area for your sand, but it seems to be a similar concept...

[MarkS]

LOL

Yeah, pretty close. The only thing is that it is going to be so heavy that I would hesitate to make it a HOB filter. It would either crack the tank or break under it's own weight. You're talking about 50+- pounds of sand + water. I would not want that hanging on my tank...

Mark

[RobG]

Point taken... That's the reason I haven't added a hang-on refug to my tank yet... I don't like the thought of all that weight against pulling down on the glass. It's just asking for 90 gals of water on my floor, not to mention fish, corals etc...

[Boatwizard]

MarkS, what I was taking about is a CC or sand bed that only flows 10-20 gallons a day through it.
A sand bed filter passes 50-200 gallons an hour.

The only question I have about your design is, would the water flow fron the overflow stir up the sand and wash it into the sump?

[MarkS]

That's a good point BW. I am trying to figure that out.

Mark

[Boatwizard]

MarkS, Ive got it, finally figure out a system that would work and be cheap to make. It based mainly on your idea. I hope to have a larger working model in a few days, it seems to work great in small scale. E mail me your address and Ill get you some drawings, I have no way to post pics on the net. Thanks

[Neal359]

whay not just get 100 yards of black air lining and wind it in a 5 gal bucket have it gravity fed with a comtroli nob to regulat the flow and have it empty in you sump semms much ezer no pumps needed

[Water World]

What if you took a 5 gal bucket with a lid that sealed. Drill two holes in the top about 1" or larger and fit two PVC fittings one for intake and one outtake (flow). The only difference is the out take would have a pipe buried most of the way down so that water would have to flow down through the sand before exiting up throught the the pipe going to the sump or what ever.The only pressure on the system would be the gravity from the overflow box...and you could tee that off so that most of the flow would go to the sump...
Liked your Ideas MarkS !!!

jc

[triggers1]

What if you took a 5 gal bucket with a lid that sealed. Drill two holes in the top about 1" or larger and fit two PVC fittings one for intake and one outtake (flow). The only difference is the out take would have a pipe buried most of the way down so that water would have to flow down through the sand before exiting up throught the the pipe going to the sump or what ever.The only pressure on the system would be the gravity from the overflow box...and you could tee that off so that most of the flow would go to the sump...
Liked your Ideas MarkS !!!

jc

check out for a sulfur denitrator

[CSeaSee]

Stop marketing your products on this site, or contact the administator and become a sponsor.

[zhenya]

Stop marketing your products on this site, or contact the administator and become a sponsor.

I agree, Carl, and I removed that link. Lets consider this a mistake for now but if I see more of this then I will have to revoke posting privilleges. And I hate doing this...