[Hormigaquatica]

Run line between 3 'add-on' RO canisters, plus a feed line, and a drain.

Hook a small maxijet up to the feed line, with a flow restricter valve in the line. An aqualifter might work here too, though Ive never tried it- I think the flow would be too slow though.

1st canister: Sulfur media
2nd canister: Crushed coral/Calcium reactor media (to adjust pH)
3rd canister: Granular activated carbon (to help remove hydrogen sulfide)

Note, you can get refillable media canisters (like what DI media comes in). I would suggest using those to put your media in, just to prevent any particles from clogging up the lines.

Test the effluent coming out of the reactor after a week or two; if you still have high nitrates, turn the restricter valve and reduce the flow through the reactor. If it comes out clean (or real close to it) then leave it be.

One thing to note, I think its better to run the effluent into a sump, rather than directly into the tank. That will allow for more aeration and reduction of any potential Hydrogen sulfide produced by the reactor.

Its worked pretty well for me and for people Ive put them together for anyhow.