denitrification

[jimdogg187]

I run a fish only marine tank. 125 gallon. 2 eels, 3 triggers one very large lion and one porcupine puffer. I've been working really hard at lowering the nitrate levels. I can't get them below 80ppm. I already invested a ton of cash in a pro clear wet dry filter so I am reluctant to switch over to a live rock/sand set up. I also use a berlin skimmer. So.. do these "denitrators" work? If so, how difficult are they to use? Which one should I buy if they do work? Please give me all the information anyone has to offer. Thanks, Jim

 

[Stryker]

Why not add *some* live rock? I know its fish only but the live rock could add to the decoration a little and any added will help towards lower nitrates....

I know you know this so I'm just wondering why not?

All I've read about denitrifiers is the horror stories in which they've some how leeched the nitrates back into the tank On those types or on the coil types how for no reason they stopped working. If you employ any kind of denitrifier other than LR, I'd suggest you get one of those nitragen monitor/alarms.

 

[jimdogg187]

Thanks for the help. I already have some live rock, but not enough by far. I think buying more will be my next move. But will the live rock really give me that much of a drop in nitrate with my filtration system the way it is?

 

[Navarre]

I dont know much about wetdry filters but unless these wet/dry fiters actually reduce nitate then the liverock has to deal with the nitrate being created by the filters as well as the nitrate thats being created by the liverock itself.

There are other denitrifyers that are cheaper and look good in the tank. Macro algea, mangroves are both very good at reducing nitrates and the fish you have wont harm these at all. Some macro algeas look very attractive in tanks.

 

[impur]

My first inclination is that you are overstocked. The porcupine puffer and lion fish are messy eaters and feeding them would result in a lot of uneaten food that breaks down producing your nitrates. Without a good cleanup crew (which you can't keep with those fish) or some quality live rock, I don't see how you can effectively reduce the nitrates AND keep them down for an extended period of time without something like weekly WCs. Do you have a sump? Fuge? What other kinds of filtration do you have?

 

[jimdogg187]

Right now I have a wet dry filter rated for a 200 gallon tank with 2 rio 2500 pumps. I think the filter is supposed to go through about 900 US gallon per hour. I understand what you said about the puffer and lion. When I first started out with those fish they were really messy. Now I feed them squid and salmon and they swallow the chunks whole. Maybe you're right, the tank might be overstocked. I did a huge water change today and added some of the new amquel plus nitrate remover. The nitrate is down to 20 ppm. I will continue to do 25 gallon per week water change and get like 40 lbs of new live rock. I'll see how low I can keep it for the next 2 weeks. Thanks very much for your reply. Anyone else have any helpful hints?

 

[lavan]

hi,

here's what i know from what i've read and my experice.

wet/dry filters are highly efficient at reducing amonia and nitrate, so much so that once established that will start producing a high amount of nitrates.

as the conversion from nitrates to nitrogen has to be in a low oxygen environment for the bacteria to colonise and use up nitrates. you would need a large amount of live rock with a slow enough flow through the rock so that the oxygen becomes depleted and allows an anerobic(not sure if' it's that what always got mixed up) enviroment to take place.

people are now doing dsb's and they can provide the anerobic enviroment to complete the nitrogen cycle, but could be a problem in the future as they are a sink for all waste, and could die off and kill tank, does take a long time 5 years +., you'll know when your dsb is dying as you will have a major algal growth.

other way is a denitrator, they are able to provide the necessary environment for the bacteria to colonise and finnish off the nitrogen cycle, can be expensive as they require food to kickstart them,such as aquamedic who use deniballs. can be quite expensive but takes 8 weeks to kick in, largest one i know is the aquamedic nitraducter, i stupidly bought one as it's overkill for my 20gallon nano and not sure what to do with it.

could use an algal scrubbing method, where you get algae to remove nitrates, aquatic eco systems do one, i've read posts from people who have one and they seem to work really well, but again are really expensive.

or could do a diy system that use's the best bits of all the different methods, i'm thinking of getting rid of my denitrator and trying out algae and mangrove plants and see how that goes,

hope this helps

 

[Navarre]

I have several types of macro algea and mangroves alonside my Liverock. Does wonders for the nitrates B)

 

[impur]

Navarre is right, a fuge with macro is the best way to remove nitrates. You might look into incorporating a 20-40 gal fuge into your system. This will also help by increasing your total water volume.

 

[jimdogg187]

Thanks In fact, I just tried that. I spent over $300.00 American dollars on a new system with a skim box. But.... I discovered the hard way that I cannot use two skim boxes on the same tank. There is no other way for me to get the water from the display to the refugium. I could set up a two level system where the fuge is below the wet/dry but that is impossible with my current set up. Not enough room. I'm totally pissed I spent all that cash. So, I'll stick some macro in the sump part of the wet dry, slap on a poewr compact and call it a day, I hope there is enough room in there though. The ammount of macro I can put in the sump may not be enough to make a difference. But now I have all the filter equiptment to start a reff tank. I'm gonna go about 55 US gallons. But buying all the rock and lights will set this project back a couple of months. But all in good time... Jim.

 

[gazza3535]

I have had a aquamedic denitrifier, a sera denitrifier, i had both of them up and running for 6 months (not at the same time) and i tested the water going into them and the water coming out of them RESULT exactly the same, save your money, get a sump with a dsb in it and lots of seaweed, then just wait for it to do its stuff, hte only thing is that the sand in the dsb needs to be the sugar sized type do not use coral gravel or any thing with bigger grain sizes

 

[ste2k3]

I'd go with a refugium as this has the added advantage of being a much simpler piece of kit than some of the other methods.

gazza3535- did you have the denitrifyer running with a probe or was it just a drip rate?

ste

 

[ostrow]

Fuge would help but you know, that W/D is probably really a factory. Sorry to say it dude, but you are likely to end up having to shell out lots in expensive equipment or at least gradually convert to live rock.