Sulfur denitrator experiment

[Delphinus]

Day 23

Pheh, this is getting a little past ridiculous now.

I don't have a very good nitrite test kit, but I do have nitrate/nitrite test strips, which do at least confirm presence of nitrate and/or nitrite and useful for observing trends but I've found the numbers corresponding to the colour chart to be innaccurate so I don't use the test kit for determining absolute values.

However it does confirm the presence of nitrite in the reactor, and has been showing this for almost a week since I started using it. No reduction in nitrite level, in fact, the colour for nitrite is off the chart.

I last tested nitrate of the reactor at day 18 and it was still off the chart (i.e., >100ppm nitrate). However I wonder if a nitrite reading would throw off this reading. I haven't been able to procure a proper nitrite test kit, if I have time to pop into Gold's on Friday I'm picking one up (all other LFS's I've tried are either sold out or don't carry Salifert nitrite kits). However I'm somewhat leery of spending $30 on a test kit that I'll never again use after this little sulfur experiment...

I expected two outcomes - the first and more optimistic was that this would prove to be viable for me. The second and less optimistic was that it would still work, but the small volume of media I'm using would prove to be ineffective on a 115g overall volume of tank. Frankly I didn't expect at all that it would seem to be incapable of growing the requisite bacterial colonies and be completely ineffectual as a result. I'm now wondering if there is something about how I've set it up, that is incorrect, or perhaps sub-optimal for running a sulfur reactor. I really wish I could see a working model in person .. I'm basically at a loss.

In the last week, I have run two 25% water changes (I don't really have the means to do a water change larger than 30 gals, I don't have a large enough reservoir to make more makeup SW) and that should put the tank nitrate level to approx. 40ppm from the initial 75ppm (75% of 75ppm =~ 56 ppm, 75% of 55ppm =~ 42 ppm), I've also moved my mangroves over and planted them in the remote-DSB, I've also made a chaeto cage and moved some chaeto onto this tank so I'm now throwing all I've got at this tank in an effort to get the nitrates down to a tolerable level .. there is a point of diminishing returns though and I don't mind admitting that I wish this sulfur reactor would kick in at some point. 3.5 weeks and no positive trend yet ... well we'll see where this goes. Maybe it's just me, and it's just not going to work. I'll give it a few more weeks but I guess there's no point in more updates at this point until there's actually a change to report on.

[andresont]

thank you for keeping this thread active !
I was just wondering:
How much media do you have in your chaimber?
how much flow is going through?
do you recerculate water inside the unit?
Thank you.

[Delphinus]

Hi,

The volume of media is around 1750ml (so just under 2 litres), which works out to about 1/3 (give or take) of a 1 gallon container of Caribsea LSM.

Flow rate is one drop per 2 to 3 seconds. I haven't worked out what that corresponds to in terms of ml per minute. I think I should work that out, I'll measure how long it takes to fill a 15ml measuring spoon tonight and post back here as that's probably good info to have to help determine whether something is set up right or not.

The water is being recirculated in the first chamber (the sulfur media only) by a mag2. The second chamber (ARM media only) is single pass.

One thought I had is that it's very difficult to determine how well the mag2 is pushing water through the media. I was wondering if it's possible that it's blocked and maybe that could explain things a little? Unfortunately I haven't worked out a way to figure out if there is flow through the media. If I blow bubbles into the intake, I could see where the bubbles go, but then I'm introducing air into the chamber and I would have assumed that's a no-no. But maybe the mag2 isn't enough, maybe it needs a stronger pump to push water through the media.

Also it's a downflow style reactor, I wonder if an upflow would be better.

[andresont]

"One thought I had is that it's very difficult to determine how well the mag2 is pushing water through the media."

The way i see it you doing everything right. lets waite and see.
Perhaps you could put a "T" with a vlave in the recirculation line to see how much you actually recirculating (instead of blowing air in the unit).When you open that valve you could get an idea of how much flow you get or at least you know that Mag pump is has good flow.
Other then that i thank you for keeping us informed.

[Delphinus]

Unfortunately I don't have a recirc line on this reactor.

Anyhow I did blow some air in. Had to open my valve and reset it afterwards. But it did show the pump is running.

Tomorrow is day 28 -- four weeks and counting. Nitrates still off the chart, nitrites still off the chart. I'm about ready to give up. I don't see any downward trend in the numbers. I don't see how reeferaddict could have such profound results in a month.

Should have gone zeovit when I had the chance. My poor tank.

I suggest to anyone reading this, don't bother with sulfur denitrators, unless you're willing to wait 15 years to see results. At least for me it's just like the Calfo DSB in a bucket idea. .. it just doesn't work.