Dose Triton from another room with one dosing pump

[67Incognito]

Hey everyone! I'm new to reefing and currently laying out a 300 gallon reef tank. I am leaning toward using the Triton method, dosing pump(s) and an Apex to control things. I want to put my dosing tanks and dosing pumps in a utility room that neighbors my display tank. My RODI system and utility sink are in that room. I'm wondering if I can use 1 dosing pump/line to dose RODI and the 4 Triton reagents. My thought is to run a 1/4 inch line from my RODI reservoir to the last stage of the display tank's sump. I would tee into that line with the different reagents and turn them on and off with solenoid valves. I attached a diagram of what that plumbing might look like. I know you can't mix the various reagents, so I would use the APEX to clear the line by pumping RODI after each reagent is dispensed. Doing so would fulfill my ATO and dispense the reagents through (1) 1/4" tube.

I am looking at doing it this way for a few reasons. First, it unclutters the display tank cabinet. Second, only one line would be required for the run to the display tanks, and third, solenoid valves are less expensive than multiple Dos pumps. Thoughts?

 

[DLHDesign]

Interesting idea! It would involve some slightly more complex programming, but I can't see any reason why it wouldn't work...

I've got enough spare gear sitting around (waiting for the next build) that I could likely mock something like this up as a test. If no one replies that they've done this, I'll look into giving it a shot.

 

[Reefer Reboot]

Doing so this way will make it almost impossible to accurately dispense a given amount of Triton reagents. The reason for this is because you are relying on gravity to inject the reagents. As the level of reagents drops there will be less force to inject it, thus changing the amount per given time using a solenoid. Peristaltic pumps injecting directly into the sump is still the way to go. Not the answer you probably wanted to hear but.......

 

[67Incognito]

Interesting idea! It would involve some slightly more complex programming, but I can't see any reason why it wouldn't work...

I've got enough spare gear sitting around (waiting for the next build) that I could likely mock something like this up as a test. If no one replies that they've done this, I'll look into giving it a shot.

Thank you! I was hoping that it wouldn't be a totally stupid idea. Obviously, it could be expanded beyond the 4 reagents. One concern is the dependability of the solenoid. You wouldn't want any one of them to stick. I guess you could add flow meters for redundancy, but then it's more complex and expensive. Not sure it's worth that.

 

[DLHDesign]

The reason for this is because you are relying on gravity to inject the reagents.

There's a dosing pump at the "end" of the chain, which should draw the same in this setups as if it were only a single reservoir.

This actually has a better chance of getting the right dose into the tank from what I can figure. That's because the RO/DI water would flush the full length of the tube, so you wouldn't have any reagent left in the line.

 

[67Incognito]

Doing so this way will make it almost impossible to accurately dispense a given amount of Triton reagents. The reason for this is because you are relying on gravity to inject the reagents. As the level of reagents drops there will be less force to inject it, thus changing the amount per given time using a solenoid. Peristaltic pumps injecting directly into the sump is still the way to go. Not the answer you probably wanted to hear but.......

I'm not suggesting that you let gravity do the work. There's still a parastolic pump. It's just that there is only one.

 

[Reefer Reboot]

Okay, second thought. Reagents solenoids 1-4 open, RODI solenoid closed, should pull equally from the four reservoirs. Try it out and let us know.

 

[DLHDesign]

I guess you could add flow meters for redundancy, but then it's more complex and expensive.

Let's see; if we just compare retail pricing:

DOS - $300ea x 2
Total = $600

vs

DOS - $300
1/4" flow meter - $20ea x 4 = $80 (ATO wouldn't need one; salinity probe can do that job)
SV-1 Solenoid - $30ea x 5 = $150
FMM - $100 x 2 = $200 (need the second one to get the 5th ACC port; 1Link module is $150)
Total = $730

Seems like even with flow meters, there is still a noticeable cost savings. And you end up with 4 extra FMM ports; nearly an entire module's worth of functionality!

EDIT:
Gah - forgot in my haste that the second option still requires a dosing pump. This could be anything, really, but to get the same features, we would want to use a DOS as well. Adding that in will obviously drive the price over the edge. Dropping the flow meters doesn't really help enough either since you need the two FMM's anyways... :-(

 

[DLHDesign]

Reagents solenoids 1-4 open, RODI solenoid closed, should pull equally from the four reservoirs.

That would mix the reagents; which you generally don't want to do. The idea would be to stagger the dosing times and add a flush of RO/DI in between. E.g.;
- Dose #1
- Flush
- Dose #2
- Flush
- Dose #3
- Flush
- Dose #4
- Flush

Each flush would pull enough RO/DI to fill the line all the way to the dump point (so that no reagent remains in the tubing). That will vary from setup to setup based on the run length, of course, but should be easy to figure out.

 

[67Incognito]

That would mix the reagents; which you generally don't want to do. The idea would be to stagger the dosing times and add a flush of RO/DI in between. E.g.;
- Dose #1
- Flush
- Dose #2
- Flush
- Dose #3
- Flush
- Dose #4
- Flush

Each flush would pull enough RO/DI to fill the line all the way to the dump point (so that no reagent remains in the tubing). That will vary from setup to setup based on the run length, of course, but should be easy to figure out.

Ya...exactly what I was thinking. This could be done with two-part instead of Triton if that's what ya want to do.

 

[DLHDesign]

So, after my cost review, I think it comes down to what you're looking for in your setup. If we add an ATO to #1, that adds another $200 to the cost. With #2, you would add $100 (drop an FMM; add the ATO). At that point, you not only have a reagent dosing solution with both options, but also an ATO solution. When you get to that "apples-to-apples", your costs are #1 = $800 and #2 = $750 (without flow meters). You could add a single flow meter (which serves to turn everything off if things don't make sense) and be at $770...
So $30 savings. But you also (with #2) get less module space, cleaner tubing, and another 2 FMM ports for other things (level sensor in the ATO chamber, for example).

 

[67Incognito]

Let's see; if we just compare retail pricing:

DOS - $300ea x 2
Total = $600

vs

DOS - $300
1/4" flow meter - $20ea x 4 = $80 (ATO wouldn't need one; salinity probe can do that job)
SV-1 Solenoid - $30ea x 5 = $150
FMM - $100 x 2 = $200 (need the second one to get the 5th ACC port; 1Link module is $150)
Total = $730

Seems like even with flow meters, there is still a noticeable cost savings. And you end up with 4 extra FMM ports; nearly an entire module's worth of functionality!

EDIT:
Gah - forgot in my haste that the second option still requires a dosing pump. This could be anything, really, but to get the same features, we would want to use a DOS as well. Adding that in will obviously drive the price over the edge. Dropping the flow meters doesn't really help enough either since you need the two FMM's anyways... :-(

I still like it though. You would still have one side of the Dos that you could use for something else, or keep it as backup. In my case, where it will be in another room instead of under the tank, it's easier to service and very easy to expand.

 

[DLHDesign]

You would still have one side of the Dos that you could use for something else

Right - forgot about that. Clearly I have a hard time remembering DOS pumps for some reason... ;-)

I've got a few solenoids and a flow sensor on the way (something I was going to pick up eventually anyways). I've already got the FMM, DOS, and other stuff. I'll be sure to post an update once I've had a chance to test it out!

 

[Larry L]

You don't have to use DOS dosers with the Apex, there are lots of good peristaltic dosers available for $100 or way less.

 

[DLHDesign]

You don't have to use DOS dosers with the Apex, there are lots of good peristaltic dosers available for $100 or way less.

True; I've gone through several, in fact.
With the new tank I'm setting up, however, I'm switching to the DOS. Mostly because it keeps a log of how much fluid it has dosed into the tank and when. And while other dosing systems may be able to do this (and/or the flow meters could replace that feature), having all the data in the same system will allow me to see the full impact of my dosing, and only have to look in one place to do so.
But your point is certainly true - if your goal is cost reduction, there are cheaper options.

 

[Larry L]

The idea would be to stagger the dosing times and add a flush of RO/DI in between. [...] Each flush would pull enough RO/DI to fill the line all the way to the dump point (so that no reagent remains in the tubing).

Also be careful to do the math with the total number of doses per day, the total amount of reagents dosed per day, and the total amount of R/O needed for all the flushes, and make sure that doesn't exceed what you would normally need to add each day due to topoff. E.g. 20 feet of 1/4" Mur-lok is going to need about 90 ml to flush completely.

 

[DLHDesign]

make sure that doesn't exceed what you would normally need to add each day due to topoff

Indeed - good point. Both of our tanks are large (mine is "smaller" at 180g+), so 100ml+ of RO/DI is well under the top-off volume the tanks will need. In my case, my dosing station will be only a few feet away from my sump.

Still waiting on the pieces to arrive; sometime this weekend...

 

[Larry L]

100ml+ of RO/DI is well under the top-off volume the tanks will need

Right, but using the example of 20 feet of line that's roughly 100 ml per dose+flush. I have calcium, alkalinity, and vinegar each set up to dose every 15 minutes throughout the day, so in one day that would be 288 dose+flush cycles, or about 7.6 gallons.

 

[DLHDesign]

I think if you're dosing that often, this solution would not be a good fit for you and your tank.

Note also that there's still the other dosing pump. If we were to switch out RO/DI water with fresh saltwater, you could use that other pump head to pull water out of the tank. At that point, the dosing setup would combine to also be an AWC system - all with a single DOS (or whatever other dosing pump you saw fit to use).

 

[DLHDesign]

Finally got around to testing this concept. The POC worked so well that I went ahead and plumbed it into my DT:

I put the ALK and CA on one pump, MG on the other for now. I could have put all three (or more) on one pump, but I only ordered three solenoids for the test.
Rather than draw from an ATO reservoir (which is out in the garage), I ended up just running the "flush" line back into my sump. No need to worry about any kind of salinity swing that way.

This is about as good a visual I can provide on how it's working:

Each spike is either ALK or CA (they alternate) followed by a "flush" execution.
The dosing time and amount is controlled using an "OSC" (oscillate) command as you would for a normal dosing pump program. Except instead of turning on a pump, it opens the appropriate solenoid. Any time a solenoid is open, the dosing pump turns on. The "flush" procedure is based on a "Min Time" command - a virtual outlet is told to open any time either the CA or ALK are open, with an additional "Min Time" to ensure that the entire line gets flushed (the DOS defaults to 25ml/min when told to just be "on"). The actual "flush" solenoid is hooked up to that virtual outlet, but also told to remain closed if either of the other two are open. The net result of this is that it stays closed while dosing the additive, and opens as soon as it's closed - remaining open for the remainder of the "Min Time" defined. Finally; I added in sensors to check the container levels; if they are empty, the solenoid stays closed (and I get an alert).

In the POC, I had a flow meter on the "out" side of the pump, but it never registered any flow. I'm pretty sure (reading the docs) that is due to it requiring a minimum pressure/flow rate - and the dosing pump just isn't getting there. Ah well; I wanted the flow meter for my RO/DI anyways.

If all I were doing with this were dosing in 2-part like this, it likely wouldn't be worth it cost-wise. But I can extend this system to include the four Triton additives I'm planning on simply by purchasing the additional solenoids (and a 1Link in order to get two more 24V outlets; I have 2 open in my current setup currently). I also don't get all the detailed reporting that the DOS can support if you use the normal method of programming it. Had I not already had the DOS, I likely would have just picked up a BRS top-off dosing pump and adjusted the timing (cut the "open" time in half since it's a 50mL/day pump).