Nitrates are KILLIN me! Tried EVERYTHING!

[Domboski]

ohh so thats how u do it dom no wonder i saw that long tank u had in the basement what if u dont have the space than what

Well that trough was more like a refugium. A pool filter would not take a up as much space I only recommended a sand filter because of the size of his tank.

 

[Domboski]

Wow, that confuses me. I would have thought the pool filter sand would end up being a nitrate factory? I certainly have the space as my 100 gal sump is in my basement beneath the tank in my living room. BUT, if the nitrates are trapped by the sand and the water continually runs through the sand it seems to be this would increase the nitrates? Please explain if you don't mind how it would reduce them.

Okay now I have "skimmed" through your thread so again pardon me if I repeat some things (some are intentional as you'll see).

1- When I skimmed your thread I did not see any reference to filter socks. Maybe you have them but if not make sure all drains into the sump have filter socks and I also have one on my skimmer return.

2- I'm not sure if you got rid of the chaeto but if not, do it. I had a lot of trouble with nitrates and phosphates several years ago and when I got rid of the fuge my problem went away. The Live rock you have is mainly helping you keep ammonia down. I'll explain that in a minute but I think Boomer has already done that in this thread.

3- This is a bit unconventional but something I've been doing lately that has helped and I did it based on a tank crash another experienced reefer I know had. Make sure there are no "dead zones" of flow in your sump. Add powerheads if you need to. Between the filter socks and your awesome skimmer (I use ASM skimmers on all of my systems) nothing should be settling in your newly set up sump.

4- I'm a fan of running carbon and using UVs. You would need a significant UV for your system (75 watts being fed at 480 GPH) but it will help with cyano. This step is not necessary for Nitrates. I just mentioned it because you seem to go all out to set things up so I'm mentioning this as a personal preference of mine.

5- This is the explanation you were really looking for. As long as you don't have a lot of particles being introduced (even if you do as long as its not rotting food or dead fish its still wont become a nitrate factory) into the pool sand filter it will not become a nitrate trap and here is why. You went bare bottom because many reefers believe a sand bed traps detritus and so forth. There are a number of discussions about this on the web so I am going to give you my opinion on it short hand. Its very difficult to maintain a sand bed and one that is not deep enough is not going to help with nitrate removal very much. What your missing out on though by running bare bottom has been mentioned by boomer. Here is his quote:

There is no sand to stir. Barebottom.

That is most of your issue, as you more than likely have little surface area for facultative anaerobic denitrification to take place and where your refugium and current denitra-unit can not handle the load. Your LR is doing much of nothing and as suggested may be leaching out more NO3, as there is little facultative anaerobic denitrification. And to add by others to much playing around with the system, to try and fix something. Your issue is common to many BB tanks. This was reason years ago many left the BB tank and went to SB tanks, as many BB tanks or what is coined "nitrate factories"

So basically what you create by adding a sand filter is what boomer is talking about here. The best part of the pool sand filter is you can maintain your "Remote Deep Sand Bed (RDSB)" much easier than having it in your display tank and gain all of the benefits of anaerobic denitrification. You can backwash every few months to remove any particles that may have been captured in the sand (shouldn't be much if you follow my recos for 1-2-3 above. There are other ways to make sure you keep your sump clean that I didn't mention but that's how I handle mine). You can buy a pool sand filter used on craigslist and other sites sometimes for as little as $30. If possible for your system I'd get one that can hold 250 lbs of sand since you have the space in the basement.

6- Finally just be patient. You need to let your system mature and give time for all of your system modifications to do their thing. Your rock from your FOWLR are probably loaded with NO3 as mentioned by others. It will take time between water changes and the other mods you have done to take effect and remove everything. Your skimmer and filter socks are preventative measures for introducing new Nitrate to your system and not helpful in removing whats already there. A pool sand filter (RDSB) once cycled, will remove nitrate leaching from the rocks or wherever its coming from in your system and in combination with water changes should drop your levels significantly.

I hope this helps. This is my personal way of dealing with Nitrates so its not the only way. I don't like dosing and always prefer natural ways of running my systems. I have deep sand beds in my display tanks (more because I think its better for the fish I like to keep rather than Nitrate removal) and also have pool sand filters. Some of my NJ buddies call me "sand man" for a good reason and its not because I have a nasty cutter and close games for the Yankees :lol2: Like I mentioned earlier, not only will the RDSB help lower your nitrates significantly, you'll be shocked how it polishes off your water too. So to sum it all up, if you have the space you should run one. Its simple and beneficial IMO.

Its pretty late/early so if I left out any details you need let me know

 

[mellotang]

Isn't the whole point of the DSB to create a ANEROBIC zone in which anaerobic bacteria consume the nitrate??? How do you create that in a pool filter where the sand is continually tumbling around? Wouldn't that create AEROBIC bacteria, which produces nitrate as a byproduct of breaking down waste.

 

[Domboski]

Isn't the whole point of the DSB to create a ANEROBIC zone in which anaerobic bacteria consume the nitrate??? How do you create that in a pool filter where the sand is continually tumbling around? Wouldn't that create AEROBIC bacteria, which produces nitrate as a byproduct of breaking down waste.

250 lbs of sand is not tumbling. If you use the right flow by the time the water gets through the first few inches of sand it is oxygen depleted and enters the ANEROBIC ZONE. Similar to how a denitrator works.

 

[kaOzGrUnT]

I looked over the replies and did not see one person mention this, your iwaki 40rlt only pumps 730gph.... Your tank is 200 gallons, you need to have a 10x overturn. You need a pump that has a return of at least 3000gph because of your head pressure of 8 feet (I am assuming for what I see from your setup from basement to living room).
You could have the best filtration system but if you are not feeding it with the water it needs to filter then your system is useless.
Let me know how it goes.

 

[waynotcars]

There is a closed loop system with six outlets running on a Mag 24. There is a LOT of water movement.

 

[kaOzGrUnT]

Yes, in the tank, no through the filtration.