robert
Valuable Member
(hey - move this to DIY - i goofed)
I see a lot of interest in bio-pellets and vodka dosing so I thought I would share my DIY sulphur denitrator.
I've been running this for at least 18 months - maybe longer. I don't touch it, no adding media, no adjustments no dosing - it just works...
I have about 170 gallons total water volume - 115 display, 45 gallon frag tank and maybe 10 gallons in a 30 gallon sump.
I'm heavily stocked - lots of good sized fish - 4 BT anemones - a crocea - and a pretty diverse mix of some pretty big LPS and more recently SPS corals and zoas. My frag tank is jammed. I feed hard - really hard - and I run an under gravel system.
Despite this nitrates are never a problem.
I tried vodka dosing and after that bio-pellets - neither worked well for me - I probably just didn't know how to use them correctly but I had all the problems you commonly read about.
So here goes -
The two main components - a wide mouth water bottle (~$12) and a cheap 100gph foam internal tank filter (~$10). remove the foam block from the filter but put back the plastic foam holder (this keeps stuff from getting in the pump impeller). Insert the pump so that the extension goes down the handle of the plastic water bottle. This holds it in place.
Pile in the media - it should be all mixed up - (those sulphur denitrators showing separate layers of crushed coral and sulphur are not doing it right.) below shows the media and pump placement.
The top is simply the top that comes with the water jug. You need to take the gasket that come with the top and cut a circle out of the center of it so that it can still slip when tightening the top. Inside this cut out area, drill three holes in the plastic lid. One for the power cord and two for the airline tubing which carries water into and out of the denitrator.
I went to home depot and got a couple of rain-bird drip irrigation adapters that fit the airline tubing. and glued those through the lid so that I can push on and pull off the tubing as needed.
on the inside, attach a length of airline tubing to one of the holes, to carry water through the media to the bottom of the bottle. This is the water intake. The other hole doesn't need tubing on the inside as it will carry water from the very top of the bottle back to the skimmer intake. Make sure this outflow hole is flush with the top and doesn't extend on the inside as you don't want any air gap in the bottle.
Cut the plug off the pump, feed it through the third hole and reattach the plug. I used expoxy formulated for plastic to make the holes watertight. I sleeved the holes with pex tubing for strength, but you simply need things to be watertight.
Screw on the lid good and tight. If the lid leaks, fill the seam between the lid and bottle with a bead of plumbers putty and wrap with that stretchy silicon tape that Home depot has in the plumbing section.
Your done. I take my input water from a tee from the pump driving my sump return. You need a reliable input flow. On the outflow, place the tube carrying the return water back to the sump close to the skimmer intake.
Now in my pictures I show clear airline tubing - I found the black tubing with a soft natural rubber feel that top-fin sells cuts down on crap growing in the lines and reducing flow.
Pay attention to your alk. the sulphur denitrator eats alk. I have to add a scoop of sodium bicarbonate per day to keep my tank at 7, on the plus side calcium is added by the denitrator - so it won't drop as fast.
Most descriptions of sulphur denitrators say to run at 1 drop per second until the output clears of nitrate. I found this causes most of the complaints with this set-up. Its just wrong - let it run wide open - the airline tubing will restrict the flow to the proper rate. (I'll measure my outflow and post it this weekend)
It will cycle in a week - maybe two - and your nitrates will drop - 60 points in a month was my experience.
Cost: 5.0 gallon jug with an internal 100 gph recirculation pump for ~25 dollars. Media was 2 liters of seachem denitrate, (~$17), 1/2 gallon carribsea sulphur (~$18/gallon) and a bag of coral chunks ~$10/half gallon).
I see a lot of interest in bio-pellets and vodka dosing so I thought I would share my DIY sulphur denitrator.
I've been running this for at least 18 months - maybe longer. I don't touch it, no adding media, no adjustments no dosing - it just works...
I have about 170 gallons total water volume - 115 display, 45 gallon frag tank and maybe 10 gallons in a 30 gallon sump.
I'm heavily stocked - lots of good sized fish - 4 BT anemones - a crocea - and a pretty diverse mix of some pretty big LPS and more recently SPS corals and zoas. My frag tank is jammed. I feed hard - really hard - and I run an under gravel system.
Despite this nitrates are never a problem.
I tried vodka dosing and after that bio-pellets - neither worked well for me - I probably just didn't know how to use them correctly but I had all the problems you commonly read about.
So here goes -
The two main components - a wide mouth water bottle (~$12) and a cheap 100gph foam internal tank filter (~$10). remove the foam block from the filter but put back the plastic foam holder (this keeps stuff from getting in the pump impeller). Insert the pump so that the extension goes down the handle of the plastic water bottle. This holds it in place.
Pile in the media - it should be all mixed up - (those sulphur denitrators showing separate layers of crushed coral and sulphur are not doing it right.) below shows the media and pump placement.
The top is simply the top that comes with the water jug. You need to take the gasket that come with the top and cut a circle out of the center of it so that it can still slip when tightening the top. Inside this cut out area, drill three holes in the plastic lid. One for the power cord and two for the airline tubing which carries water into and out of the denitrator.
I went to home depot and got a couple of rain-bird drip irrigation adapters that fit the airline tubing. and glued those through the lid so that I can push on and pull off the tubing as needed.
on the inside, attach a length of airline tubing to one of the holes, to carry water through the media to the bottom of the bottle. This is the water intake. The other hole doesn't need tubing on the inside as it will carry water from the very top of the bottle back to the skimmer intake. Make sure this outflow hole is flush with the top and doesn't extend on the inside as you don't want any air gap in the bottle.
Cut the plug off the pump, feed it through the third hole and reattach the plug. I used expoxy formulated for plastic to make the holes watertight. I sleeved the holes with pex tubing for strength, but you simply need things to be watertight.
Screw on the lid good and tight. If the lid leaks, fill the seam between the lid and bottle with a bead of plumbers putty and wrap with that stretchy silicon tape that Home depot has in the plumbing section.
Your done. I take my input water from a tee from the pump driving my sump return. You need a reliable input flow. On the outflow, place the tube carrying the return water back to the sump close to the skimmer intake.
Now in my pictures I show clear airline tubing - I found the black tubing with a soft natural rubber feel that top-fin sells cuts down on crap growing in the lines and reducing flow.
Pay attention to your alk. the sulphur denitrator eats alk. I have to add a scoop of sodium bicarbonate per day to keep my tank at 7, on the plus side calcium is added by the denitrator - so it won't drop as fast.
Most descriptions of sulphur denitrators say to run at 1 drop per second until the output clears of nitrate. I found this causes most of the complaints with this set-up. Its just wrong - let it run wide open - the airline tubing will restrict the flow to the proper rate. (I'll measure my outflow and post it this weekend)
It will cycle in a week - maybe two - and your nitrates will drop - 60 points in a month was my experience.
Cost: 5.0 gallon jug with an internal 100 gph recirculation pump for ~25 dollars. Media was 2 liters of seachem denitrate, (~$17), 1/2 gallon carribsea sulphur (~$18/gallon) and a bag of coral chunks ~$10/half gallon).
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