High Nitrates

[flynnternet]

I'm at a loss as to why I can;t get my trates down. I use only RO water, feed every other day, and my Nitrates are still at 20ppm. I just did a water change on Sunday as well (about 20%). My nitrates never seem to go below 20, or not for quite a long time anyway.

On perhaps a related note, I've noticed my that a few of my snails have died. I had maybe 6 nassarius snails about a month ago, and they seem to all be gone now. All four of my Turbos have gone, as well as a few nerites. Only my ceriths seem to be unscathed. My three shrimp and two fish are happy, but I have seen an upsurge of algae/diatoms on the sand.

What can I do to lower my nitrates? I also want to replace my nassarius snails. ANyone have a clue as to why they may be dying? Starvation?

TIA

 

[steve-s]

I'm at a loss as to why I can;t get my trates down. I use only RO water, feed every other day, and my Nitrates are still at 20ppm. I just did a water change on Sunday as well (about 20%). My nitrates never seem to go below 20, or not for quite a long time anyway.

What do you have in the Fluval? It could easily be the source of your problem if filter pads/carbon are not cleaned regularly. They tend to trap a fair amount of junk but if cleaned weekly should be fine. With the amount of LR you have though, the added filter is not really necessary though.

Have you taken a sample of water to the LFS to see if your test kit may be faulty? It's always a possibility!

On perhaps a related note, I've noticed my that a few of my snails have died. I had maybe 6 nassarius snails about a month ago, and they seem to all be gone now. All four of my Turbos have gone, as well as a few nerites. Only my ceriths seem to be unscathed. My three shrimp and two fish are happy, but I have seen an upsurge of algae/diatoms on the sand.

The snail deaths could easily be related if not acclimated slowly enough. Many types of snails will adapt to higher nitrates if so but if not acclimated for several hours will not last that long. How's the chemistry in the tank? Alk, Ca and pH?

Cheers
Steve

 

[flynnternet]

In my Fluval I have GAC in filter bags. I had floss at one point buy took it out because I thought it would cause higher nitrates. Should I ditch the carbon? Or only run it infrequently? I've been changing it once a month. I kind of like the water movement and the added water volume (only a 1 gal or so, but worth it in my small tank)

Just tested params, and I'm at Ca 420ppm, Alk 9dKH, and a pH 8.2

The snails were added maybe 4 months ago and most lived until pretty recently (within a month). Could the acclimation really be affecting them now?

 

[jackdp]

Have you checked your freshly mixed SW just to rule out your salt mix or bad RO water. I change my GAC almost weekly but I don't know if that could be your problem. Also, make sure you've got good flow throughout the tank, the more water you can get moving through and around your LR the better the bacteria can do their job.

 

[steve-s]

In my Fluval I have GAC in filter bags. I had floss at one point buy took it out because I thought it would cause higher nitrates. Should I ditch the carbon? Or only run it infrequently? I've been changing it once a month. I kind of like the water movement and the added water volume (only a 1 gal or so, but worth it in my small tank)

That sounds fine but changing the carbon monthly should be combined with rinsing it out weekly in SW. It's what gets trapped in the filter that's the problem. There's no reason why you cannot continue as you've been doing provided you clean out the Fluval weekly, preferabley using SW.

When you change out the old carbon how much junks in there?

Just tested params, and I'm at Ca 420ppm, Alk 9dKH, and a pH 8.2

Couldn't be better

The snails were added maybe 4 months ago and most lived until pretty recently (within a month). Could the acclimation really be affecting them now?

After 4 months, acclimation won't be the issue. If the nirtrates are an ongoing issue, they won't be either really unless higher than the 20 ppm indicated. It becomes moreso a problem with sudden increases or ongoing higher levels of NO3.

With the shrimp doing well, I'd suspect something else. They are even more sensitive than snails as far as water quality. Any crabs?

Cheers
Steve

 

[flynnternet]

One crab who has evaded capture. I see him waving at me as he slips into a rather craggy piece of LR. He could be the culprit but I have never caught him out of his network of caves. Still, have supsect him for a while but he never takes any bait.

I'll definitely try rinsing the carbon weeklyin SW. Crud gets trapped in the filter bags, but the carbon stays clean. After a month of rinsing and a another water change or two, hopefully I'll see results.

I will also try testing my RO water. I've never tested it for nitrates. The TDS reading is low though, so I think the membranes are still good.

Thanks much.