Sulfur denitrater won't cycle

[klasiksb]

I tried a Midwest Aquatics SD several years ago, never got it to work. The guy at MA (forget his name) was trying to help me all along the way, but never got it working. Still don't know why. I ended up sending it back months after the 90 day refund period and got a full refund. Maybe I got a dud, i don't know. Would like to try again sometime but not sure. Hopefully your local guy will get it going for you. Interested to see what happens with this.

 

[reefslugs]

Breaking news! No my reactor is not doing better, but I got a hold of Midwest Aquatics. Very nice person who I talked to. He is also confused why my reactor is not working, after asking me several questions. So he asked me for my address and he is going to send me some bacteria to inject into my reactor. This should really kick start the thing off. He told me after two days if I don't see any progress give him a call back. He was really a good guy to talk to.

 

[klasiksb]

He sent me bacteria as well, never did a thing. Good luck though, hope it works out.

One thing I always wondered was does temp. inside of the reactor make a difference? Mine ran out of sump in a cold basement, so don't know if that had anything to do with it or not, but might be something to think about. Since the flow through them are really slow, that might affect it?

 

[Nanook]

Is your model a recirculating design??

 

[elijaher]

That is a good question on temp.

 

[thi7b]

Up date. Still to this day I have 100% nitrites coming out. I've tried contacting Midwest Quatics again with no response. So I decided to ask a locale sulfur reactor manufacture, his opinion. I e-mailed Schplitter maker of sulfur reactors here in St.Louis. Which I told him at the time when I was looking at buying a sulfur unit, I didn't run into his product. I e-mailed him yesterday and one hour later he e-mailed me back wanting my phone number so we could talk man to man. I talked with him today, told him what reactor I bought. I told him their instructions are the same as his. He asked me several questions, like are you sure the pump works, is it circulating, extra. He as you all could not come up with an answer. He ask me to bring my reactor over to his place this week and he and his crew will take look. Off the top of his head he thinks my sulfur is no good. I really am blown away by Schpitter that he would go out of his way to look at a reactor that he didn't make. I have a 90 day guarantee with Midwest Aquatics, I'm thinking of ditching the unit and buying one from Schpitter Sulfur reactors.

I have a contact number for Midwest Aquatics if you need it. PM mefor the number.

 

[Dalmerjd]

Wow, I am experiencing the exact same issues.
My reactor has been on line for four days now at 1 drip per second.
I checked the tank nitrate, it was at 5-10 as per salifert. The effluent from the reactor was way high, like over 100ppm. I did not have time to check nitrite. I would tend to go along with Randy on this one. Reason being, when you do a nitrate test with salifert kits you are supposed to wait 3 minutes for color to develop. When I did the test, the color was dark purple with in 15 seconds. This was very strange.
My friend started one up a few days before me so I will get him to check his to see what his is doing.

 

[Dalmerjd]

Curious, what/who's medias are you folks using. Just wondering if there are better or worse conbinations.

 

[riddler772]

Hi. I have been using the Midwest Sulfur Denitrater for over 3 years.They are very effective but must be monitored and adjusted correctly.First of all your test kit is not the problem.Everytime they are first started the Nitrates go sky high,for the first several days.Every three months or so they seem to crash,at least for me,and must be broken down and restarted.ASa result I have much experience with the start up procedures.Based on my discussions with Midwest over the years ,it is my belief,that the crahes are caused by the media being blocked,probably food or other crud in the water,so the circulation is decreased.The size of the sulfur media contributes to this problem.THe LSM which I am presently using is a smaller diameter than the European counterpart,and this tends to cause the blockage.The European larger diameter is frequently not available.
After the high nitrate reading on the 3rd day or so slowly increase the flow.Once the reading is 0 continue to increase until it starts to rise again.Then cut back slightly until it reads 0 again.From my experience once you smell sulfur,its best to start over again.

 

[Randy Holmes-Farley]

They are very effective but must be monitored and adjusted correctly.First of all your test kit is not the problem.Everytime they are first started the Nitrates go sky high,for the first several days.

Why do you think that? Because a test kit says so?

For the reasons we mentioned, that is probably nitrite interference, not nitrate.

Can you propose any mechanism whereby a sulfur denitrator can increase nitrate? Where would the nitrogen come from?

 

[riddler772]

Very simple answer,because it does.Check with anyone who has ever used a Sulfur denitrater of any design and see if they get the same results and reading.I suspect they will all get initial elevated readings which then go down after several days.The important point is not why this is happening but how to get your Sulfur Denitrater working.Also I forgot to mention open the vent on the top of the unit to check for a strong water flow.If the flow is not strong than the recirculating pump is airbound.Following these and my previous instructions will get your Denitrater to produce 0 nitrate outflow.

 

[bertoni]

How do you know that? As has been pointed out, small amounts of nitrite will show up as large amounts of nitrate on our test kits. It's not the measurements that are in doubt, but their interpretation.

 

[vegaskid11]

Very simple answer,because it does.

Is this like the easy button?

 

[Randy Holmes-Farley]

Very simple answer,because it does.

But you do not know it does, and I think you are wrong. You just have a kit reading, and no possible way for it to happen, while we have supplied a perfectly logical reason that explains everything you observed. Remember, this is a science forum. It matters to us, if not you.

There is a ton of information about reef chemistry that is thought by many to be clear, when in reality they misunderstand it. That includes many of the well published experts when they start to drift from their fields of expertise. That was the main reason we started this forum.

.The important point is not why this is happening

Maybe, but I think you misunderstand the process. One can easily sail from Europe to the US while still thinking the earth is flat. But if you understand it really is round, that may open up a better appreciation for the natural world, and places you can travel. Same applies here. You can get it to work, even without knowing what was happening, but knowing may allow a better appreciation for how it works and what may go wrong.

If there is not substantial ammonia or nitrite in the aquarium water, there is no nitrogen source to make substantial additional nitrate in the sulfur denitrator when starting it up. So the explanation likely lies elsewhere, and nitrite interference seems likely to me.

 

[riddler772]

I am Frustrated What Should I Do

I am Frustrated What Should I Do

This is a very simple problem made complex.The original question is "My sulfur Denitrater does not work.What should I do? " Not what is the theory of Sulfur Denitraers.If my advice is followed his Sulfur Denitrater will work.This is based on 3 years working with the Midwest Denitrater and solving the same problems that were posted in the original question.While Mr Holmes is the master Reef Chemist I am the expert at making the Midwest Sulfur Denitrater equipment work.As an aside you may be right that the Nitrate tester is reading incorrectly.I never said it was accurate.I said that every time the unit is stated for the first 3 to 4 days it reads exceedingly high.That is for the last 18 -20 times I restarted the unit the outflow initially read very high before turning to 0.Your interpretation may be correct.However that does not solve the problem of "What should I do" Slowly increasing the flow will correct the problem unless the recirculating pump is airbound.Check with the manufacturer at MidWest Aquatic and he will affirm that the initial high reading is very common.The analogy of sailing around the world while beleiving the world was flat was particularly appropriate.

 

[Randy Holmes-Farley]

This is a very simple problem made complex.

Well, I don't recall making any directions complex. My suggestions were as simple as yours, just different. I then pointed out one of your statements that I believed is wrong. Doesn't mean your method itself is wrong, but this forum strives for accuracy.

Your suggested procedure may work. So might what I suggested. In fact, just doing nothing and waiting longer may work too. It seems a number of folks have had problems even after getting advice from the manufacturer.

 

[Dalmerjd]

My H & S denitrator has been running for a week. The nitrites are off the scale high. I ran the effluent wide open and put about 4 gallons of water through it, into a bucket, until the nitrite reading was almost 0. I ran it for 24 hours at 1 drip per 4 seconds and the nitrites are off the scale high again. If I increase the effluent flow too much my redox readings start to fall off and my pH starts to drop too. If I run it into a bucket instead of back into the tank I will end up dropping my salinity by the time I get home from work(12hrs).
I am not a chemist nor do I have many years of experience. I don't understand why there is nitrites. I just want this thing to work. How do I get this puppy to work without messing up the rest of the system?
I have tried going very slow to fairly fast effluent flow with no results.
What should I do?

 

[Randy Holmes-Farley]

The issue is getting all the necessary bacteria populations in place, which takes time. Going especially fast cannot make the bacteria grow faster.

In the reduction of nitrate to N2, nitrite is a likely intermediate, just as it is an intermediate in the conversion of ammonia to nitrite:

NO3- ---> NO2- ---> N2
nitrate ---> nitrite ---> nitrogen gas

NH3+ ---> NO2- ---> NO3-
ammonia ---> nitrite ---> nitrate


The specific reaction for the known conversion of nitrate to nitrite is:

NO3- + 2H+ + 2e- > NO2- + H2O

 

[tmz]

I would not increase the flow unless I smelled hydrogen sulfide or had significantly less nitrate in the effluent than in the tank.
If the dentirator is giving you 50ppm vs 30ppm for the tank, decrease the flow. This decrease the oxygen level in the reactor encouraging the bacteria to get it from the NO3. You can drip the effluent into a bucket during cycling to avoid adding high nutrient effleuent to your tank.
Increase the flow when you are getting low effluent nitrate,(>2ppm) to avoid hydrogen sulfide production.
In my experience the denitrator will produce nitrite before dropping nitrate. I used the api test kits for NO3 and NO2. and found them sufficient.

 

[vegaskid11]

+1 ^

Do not increase your flow at all until you test 0 for nitrite (do not measure nitrate at this time). Keep the flow at 1 drip per second or less until you get 0for nitrite (1-3 days). Once you reach 0 for nitrite then start testing for nitrate, don't increase flow yet! Within another 1-3 days you should see nitrate start to quickly drop. You will want to test daily or even multiple times daily (morning, night) during this "cycle phase". As soon as you see your nitrate reading at 1-3 ppm then you can start increasing flow. Only increase flow when you test nitrate at less than 1-3 ppm from the reactor and increase the flow by only 10 percent each time.

You have to babysit this thing until you get to your max flow rate. Its not just plug and play. Maximum flow rates are suggested at 3-5x the volume of media. If you have 1 liter of media (sulfur) you will shoot for an end flow of around 3-5 liters per hour which will be achieved anywhere from 4-8 weeks after start. The time frame to get your results (under 5 ppm tank levels) will vary depending on your initial nitrate levels.