Nutrient Pulse Reactor (DIY DyMiCo filter)

[OzIA]

Yes. They are the same module/s. You have to tell the Apex that it is an ORP or pH. Then, with pH, you have two calibration options: 7.01 / 10.0 and 7.01 and 4.01.

The 7.01 would equate to 0 mV but the other two would be 175 mV (4.0 pH) and -175 (10.0 pH).

Any idea how to create a -175 mV solution?

 

[OzIA]

BRS Doser

BRS Doser

Just a few more comments on the BRS 1.1 ml doser.

I really can't believe how inconsistently these are. The delivery rate is anything but 1.1 ml a minute and that dead spot really screws up the dosing on anything less than a full revolution.

I tried to cut the carbon I was dosing so that I could make the time closer to the full revolution. It takes about 1 minute and 5 seconds for a full revolution. I tried to set it for that but I still end up with a large dose about every four hours. Check the graph out.

I am returning these and looking for a new option.

Aaron

 

[dartier]

Yes. They are the same module/s. You have to tell the Apex that it is an ORP or pH. Then, with pH, you have two calibration options: 7.01 / 10.0 and 7.01 and 4.01.

The 7.01 would equate to 0 mV but the other two would be 175 mV (4.0 pH) and -175 (10.0 pH).

Any idea how to create a -175 mV solution?

I did look into this, but forgot to post the results. There seems to be 2 common ORP solutions that are mentioned in literature. However it sounds like Neptune only recommends making your own using PH solutions and Quinhydrone. See https://forum.neptunesystems.com/showthread.php?19-Read-this-first-Probes!

I am not sure where to get quinhydrone.

Dennis

 

[dartier]

Just a few more comments on the BRS 1.1 ml doser.

I really can't believe how inconsistently these are. The delivery rate is anything but 1.1 ml a minute and that dead spot really screws up the dosing on anything less than a full revolution.

I tried to cut the carbon I was dosing so that I could make the time closer to the full revolution. It takes about 1 minute and 5 seconds for a full revolution. I tried to set it for that but I still end up with a large dose about every four hours. Check the graph out.

I am returning these and looking for a new option.

Aaron

I expect that many dosing heads are going to struggle with such low volumes. You could move to a stepper based unit, but you may still run into trouble. I have some FMI heads that are capable of dosing 1.28 uL per stroke, but those are far from turnkey units.

The other thing you could do is to dilute the carbon source so that a larger volume is dosed to help mitigate the flow irregularities. You would need to not dilute it too much, otherwise you may run into trouble with bacteria growing in the dosing container. I know that Ecodeco uses 10L containers of carbon, so I expect that their solution is fairly diluted.

Dennis

 

[OzIA]

Just finally got around to doing a little research on calibrating the ORP probes. Everything I have found uses 4.0 and 7.0 pH calibration solutions with this quinhydrone powder added. The Apex even has a calibration selection for 7.0 and 4.0 quinhydrone solutions. Again, the problem there is that I have to designate the channel as a pH because Apex won't read negative mV values when it is set up as ORP and I am sure those calibration values won't work once the channel designation is changed.

Also, another update...

The Reborn media started to clog, just like the other stuff i was using. I added a flush cycle that will run every few days, for an hour and changed the carbon I was dosing from sugar and alcohol to 7% ethanol and 3% vinegar. This also allows me to run the BRS doser longer and reduces the affect of the dead spot.

Nitrate had moved up to .75 ppm but I have been feeding a lot just to see if the filter would keep up. Phosphate is still showing at .08 so I am still out of Redfield Ratio. I ordered a Hach Meta / Ortho phosphate kit (very pricey) because I am beginning to doubt that Red Sea kit.

I still haven't set up the Dingo Down version on the other tank, mainly due to the issues that I am experiencing on the 90.

Aaron

 

[dartier]

Just finally got around to doing a little research on calibrating the ORP probes. Everything I have found uses 4.0 and 7.0 pH calibration solutions with this quinhydrone powder added. The Apex even has a calibration selection for 7.0 and 4.0 quinhydrone solutions. Again, the problem there is that I have to designate the channel as a pH because Apex won't read negative mV values when it is set up as ORP and I am sure those calibration values won't work once the channel designation is changed.

Also, another update...

The Reborn media started to clog, just like the other stuff i was using. I added a flush cycle that will run every few days, for an hour and changed the carbon I was dosing from sugar and alcohol to 7% ethanol and 3% vinegar. This also allows me to run the BRS doser longer and reduces the affect of the dead spot.

Nitrate had moved up to .75 ppm but I have been feeding a lot just to see if the filter would keep up. Phosphate is still showing at .08 so I am still out of Redfield Ratio. I ordered a Hach Meta / Ortho phosphate kit (very pricey) because I am beginning to doubt that Red Sea kit.

I still haven't set up the Dingo Down version on the other tank, mainly due to the issues that I am experiencing on the 90.

Aaron

I seem to recall that the Red Seat PO4 kit had a known tendency to read 0.08 all the time when the test kit is bad. If you search the forum you will probably find some reference in the Chemistry forum.

I wonder if your media is clogging due to too low of flow in your flush? Any idea how many GPH you are running the pump at? I would think that as long as you are able to hit the suggested GPH from the DyMiCo manual, then the media should not clog, and if it does, then the next culprit is how much carbon is being added.

Dennis

 

[OzIA]

I tested one of the other tanks, that is not running organic carbon and it tested at 0.36 with the same Red Sea test, nitrate was 12.0. I also tested some of the water from my LFS and I couldn't even read the low level. I had to test again on high level and it still came in at full color, which is 5.44 ppm. I know these kits don't test for organic phosphate and I believe this one (Hach) is supposed to.

Regarding the media and flush flow... I have come to the same conclusion: Too little flow. However, I am not sure if I can bump it up much. Currently, it looks like about 180 gpm. The flush cycle does't seem to have helped. In fact, it may be worse now, since writing that last message. I am going to open the chamber and mix it by hand to see if I can break up that slime and then try to increase the flow by changing the pump configuration. What was the DyMiCo flow rate on their system?

Aaron

 

[dartier]

I tested one of the other tanks, that is not running organic carbon and it tested at 0.36 with the same Red Sea test, nitrate was 12.0. I also tested some of the water from my LFS and I couldn't even read the low level. I had to test again on high level and it still came in at full color, which is 5.44 ppm. I know these kits don't test for organic phosphate and I believe this one (Hach) is supposed to.

Regarding the media and flush flow... I have come to the same conclusion: Too little flow. However, I am not sure if I can bump it up much. Currently, it looks like about 180 gpm. The flush cycle does't seem to have helped. In fact, it may be worse now, since writing that last message. I am going to open the chamber and mix it by hand to see if I can break up that slime and then try to increase the flow by changing the pump configuration. What was the DyMiCo flow rate on their system?

Aaron

Hi Aaron,

Hmm, are you sure about the return pump flow? Could that be GPH? The 700 model filter (which I suspect is the closest in size to yours) is set to 53 - 93 GPH

The process pump on the other hand is 106 - 792 GPH. The Tunze model 1073.03 that they use is adjustable, but they do not say what if any adjustment that it has been set to. I would expect it is probably going at max. The BETA units had a ball valve and flow meter on the process pump, but the production units do not seem to have this any longer.

I am thinking it might be your process pump being too weak? I would think that pump would have the biggest impact on keeping bacteria suspended and not congealed.

Dennis

 

[OzIA]

Yes. Sorry GPH, not GPM, obviously. The process pump is much smaller but it is running at essentially minimal head pressure so it should be running close to the 200 GPH rating. I am guessing that the flow rate of both pumps are similar. The flush pump is a Lifeguard Quiet One - model 4000, which is rated for almost 1000 gph but with all the plumbing and lift, is running the actual flow is about 180 gph.

I guess now I am not sure flow is the issue.

I am running the process pump for 30 sec, then off 2 min. Maybe I need to run it more evenly.

 

[OzIA]

Well, I pulled out about 3 gallons of the Reborn so that I could stir the rest, all the way to the bottom and then put what I removed back in. The bacteria / slime was pretty thick but not as much as I expected. It sort of looked like small pieces of wet tissue paper floating around in the water.

Flow was back up to normal after that exercise. I also checked the flow rate of the process pump and it was much less than I expected at around 75 gph. I am not sure if that was a result of the bacteria build up or if the pump was never up to spec. I think I will order in a few larger pumps. I hope this has nothing to do with the size of the Reborn media. That stuff isn't cheap and I know you have a substantial investment in it too.

Aaron

 

[dartier]

Flow was back up to normal after that exercise. I also checked the flow rate of the process pump and it was much less than I expected at around 75 gph. I am not sure if that was a result of the bacteria build up or if the pump was never up to spec. I think I will order in a few larger pumps. I hope this has nothing to do with the size of the Reborn media. That stuff isn't cheap and I know you have a substantial investment in it too.

The Reborn should work fine. It is very coarse which will leave lots of voids and should make for great flow.

I am running the process pump for 30 sec, then off 2 min. Maybe I need to run it more evenly.

The process pump should be on almost 100% of the time I would think. The only time I expect it may need to be off is during flushes, and I am not even sure if it is required to be off then. I think the sludge that you are building up is a sign of too little flow through the coarse bed.

I would suggest a Sicce Silent 2.0 would make for a good process pump. I am using Sicce Silent 3.0's for both process and flush pumps. The smaller model 700 filter uses a smaller process pump (similar to a Silent 2.0) and a larger flush pump (about a Silent 3.0).

Dennis

 

[OzIA]

I changed the pump out in favor of a slightly larger one. I am limited on my ability to install anything much bigger. I might be able to put a Silent 1.0 in but I don't think it would perform much better than what I now have.

I am getting about 125 gph and I am now running the pump 100% of the time. I guess we will know in about three weeks. That seems to be the time frame when things start to clog.

Aaron

 

[OzIA]

There is definitely a functional relationship between the amount / size of the flush and the carbon dose. You can see in the thumbnail attached, the point were I decreased the volume of the flush. ORP peak values changed significantly and started recovering about 10 minutes faster, despite the dose timing and volume not changing.

The slope also changed at pretty much the same location, although it reached that point sooner. If the value is accurate, that point is about -116 mV. Do you think that is the point where the nitrate has been consumed or where the nitrate starts being consumed? If it is the end of the reaction, I can reduce the time for the cycle to 30 or 40 minutes as opposed to an hour and still have the same effect.

 

[dartier]

It is hard to say for sure (about the nitrate being completed or just having started). I think I can detect a slight change in the slope of 3 of the last 4 peaks on the graph. I would expect the graph to rise sharply once the nitrate has been reduced.

Dennis

 

[OzIA]

I have ordered quinhydrone to calibrate the probes. I have also been able to reduce the cycle to to 30 minutes with the larger process pump, which now runs all the time. This seems counter intuitive to me that more flow is better but apparently it is.

 

[dartier]

I would guess that the stronger process pump is mixing the carbon dose better throughout the coarse bed, and making your filter more efficient in the process. It should also help with the buildup of the bacteria.

Dennis

 

[OzIA]

I did a few experiments to see if I could easily control the range of the cycle and as you can see it is possible. The first set of cycles show the 1 hour cycle. I then switched to a 30 minute cycle but the carbon dose was decrease by about 15%. I then added the 15% back, starting at the 8:00 dose and you can see the result.

In the second thumbnail, you can see that the cycles were going along nicely, then I turned off the flush to see what would happen to the slope of the curve. I even added carbon but it never really changed. This tells me that the lack of carbon is not the reason for the change in slope.

Also, I added the pH of the reaction chamber on top of the graph (62) and you can see that pH is falling which probably indicates that CO2 is building. The odor generated by this activity is also more noticeable.

Aaron

 

[dartier]

The length of time that you leave the flush pump on will determine the length of the next cycle (I think). Did you leave the flush (return) pump on longer during that last cycle, or was the only change the lack of carbon dosed directly after the flush?

Dennis

 

[OzIA]

It appears that the longer the flush cycle, the higher the ORP goes. I assume this is because the water entering that chamber has plenty of oxygen. If you flush enough water to move the ORP much beyond zero mV, then there is a longer period where the ORP value stays flat.

If you flush just enough to drive the ORP down to around zero mV, then it almost bounces back.

If you lower the carbon dose, then the ORP will recover slower and typically not reach the same negative value.

In the graphs here, (61 & 62) once the ORP reaches about -160mV, the slope flattens and even adding more carbon won't move the slope back to the more aggressive angle that was recorded when the ORP started to rise from zero mV. This tells me something in the reaction is changing. I know that we have been looking for the opposite occurrence to indicate when the NO3 has been consumed so I can't figure out why the slope is flattening.

 

[dartier]

I know that we have been looking for the opposite occurrence to indicate when the NO3 has been consumed so I can't figure out why the slope is flattening.

Ah, I think I know what you are seeing. If you go back to post #7 in this thread and look at my graph from a sulfur denitrator, you will see a similar pattern in the first 3 graphs. If I remember right, I was using ORP to control the flush in those first few cycles. The actual cycles themselves were long, multi-hour cycles. Because I was using the ORP to determine when to end the flush, and the ORP lagged, the level overshot the target by a fair amount (during the flush) and it took a long time to get it down again. During these cycles, I recorded a flattening out, then a little hump, and finally a plunge in ORP.

If I recall correctly, I think the little hump was attributed to a shift in PH (which moves counter to ORP). This effect was pronounced because of the large volume of water entering the system during the flush. Later cycles in that graph are timed flushes so a much smaller volume of water entered the denitrator.

Your large flat bottomed graph may be showing you the same thing, but you are ending the cycle before the knee is evident.

Dennis