Raindrip Water Timers--Cheapo Actuated Ball valve.

[Anonymous]

Matt, I am still confosed by how you use two to get the volumn down to 1 oz.

If the order from reservoir to tank is:

Reservoir>Valve 1>Valve 2>Tank

Start with both valves closed. Open Valve 1 for 1 minute. Close Valve 1. Open Valve 2 for 1 minute. Close Valve 2. Repeat all. As long as the two valves are not both open at the same time, the volume of liquid between Valve 1 and Valve 2 will be the amount added to the tank. If you just leave the piping between the valves, it's only about 1 ounce. You could add whatever size sealed reservoir you like between valve 1 and valve 2 to change this volume. Make sense?

It does make sense. I was thinking that you stagger the timing between the valves slightly, so that the time interval when both valves are open can be less than one minute to get the low volume dose. Can be tricky to set up, however.

Another alternative is to get a reservoir fitted with a small air hole, so that when the valve is opened, the amount that can came out is regulated by the size of the air hole. This way, you only need one valve, but you will need slightly more complicated plumbing to prevent air backflow that drains the entire tubing, such as the use of an antisophon U-tube, etc.

 

[Anonymous]

It does make sense. I was thinking that you stagger the timing between the valves slightly, so that the time interval when both valves are open can be less than one minute to get the low volume dose. Can be tricky to set up, however.

That's exactly what we were trying to do when we came up with it. I was trying to do a 15 second "open" timer. I was considering playing around with the electronics on the circuit board, but this is much much simpler. There are all sorts of dispensers that use the principle. The things that dispense bulk jelly beans, coffee, nuts, etc at the grocery store in "spurts" use the same principle.

 

[Anonymous]

Here she is, fairly straightforward, let me know if you have any questions.

 

[bleedingthought]

That does make sense now. I guess I could do dry foods that are soaking in salt water?

 

[Anonymous]

That does make sense now. I guess I could do dry foods that are soaking in salt water?

It's doable, but I wouldn't recommend leaving flake food in saltwater for hours at a time.

 

[Anonymous]

I'm guessing the reason for live food is because dead food would all be at the bottom so the first dose will be much greater than subsequent ones. This could also work quite nice for a two-part solution, although at $40 a pop per timer may be a bit pricy of an option

 

[bleedingthought]

This could also work quite nice for a two-part solution, although at $40 a pop per timer may be a bit pricy of an option

Not pricey at all if it's accurate.

 

[Anonymous]

Ok, it's not pricy compared to a perastallic (sp) pump, but pricier than me walking down stairs every morning and pouring two cups and pouring it in

 

[Anonymous]

Ok, it's not pricy compared to a perastallic (sp) pump, but pricier than me walking down stairs every morning and pouring two cups and pouring it in

They actually make really cheap peristaltic pumps for around $65 that would be ideal for dosing 2 part:

http://www.aptinstruments.com/Merchant2 ... Code=SP100

You can plug 2 of them into the same light timer and have them dose as long as you like, depending on how much you want in your tank every day.

 

[Anonymous]

Ok, it's not pricy compared to a perastallic (sp) pump, but pricier than me walking down stairs every morning and pouring two cups and pouring it in

They actually make really cheap peristaltic pumps for around $65 that would be ideal for dosing 2 part:

http://www.aptinstruments.com/Merchant2 ... Code=SP100

You can plug 2 of them into the same light timer and have them dose as long as you like, depending on how much you want in your tank every day.

I've been trying to figure out a way to do this easily. So you can dose both parts at once and set the time to run for say 1 minute and set the pumps to dispense the correct quantity over that 1 minute period? My tank is not very heavy on the Ca/Alk use, so I wouldn't need much....

 

[Anonymous]

Well Guru, you can simply calculate how much you're going to dose, then divide by the number of mL/min the pumps work at, and that'll tell you how much time you need the pumps on.

My problem is I don't know anything about those pumps, other than a basic how they work. Is that something I want to go with bigger tubing?
Also is there any reason I wouldn't want to go with a variable flow pump? It seems they're just about the same price (a buck cheaper actually)
http://www.aptinstruments.com/Merchant2 ... de=SP100VO

 

[Anonymous]

Yeah I would think variable would be better too. I don't obviously see how one adjusts it though on the pump you listed. Ahhh, I see they add $40!?!? to put a plug on it for us (as it is a DC motor).

 

[Anonymous]

Or you can just buy a wall wart (or use one of the many you have lying around if you're like me ) and strip the wires and hook up yourself. I would guess there's some sort of potentiometer on the device (or you'd hook one up) in order to vary the output, or perhaps there's some gearing ratio you can change.

 

[Anonymous]

Ok, it's not pricy compared to a perastallic (sp) pump, but pricier than me walking down stairs every morning and pouring two cups and pouring it in

They actually make really cheap peristaltic pumps for around $65 that would be ideal for dosing 2 part:

http://www.aptinstruments.com/Merchant2 ... Code=SP100

You can plug 2 of them into the same light timer and have them dose as long as you like, depending on how much you want in your tank every day.

I've been trying to figure out a way to do this easily. So you can dose both parts at once and set the time to run for say 1 minute and set the pumps to dispense the correct quantity over that 1 minute period? My tank is not very heavy on the Ca/Alk use, so I wouldn't need much....

The way we do it is to just hook up the pump, start it dosing and then measure its output. The heights of the reservoir, length of the tubing, etc, will all affect the dose rate. The numbers of mL/min on the website are rough estimates. You just calculate from there.

In the case of these smallest pumps they are dosing something like a few mL in a minute. You would probably want to run it a few minutes per day, maybe several times per day, even in a small tank.

Regarding the fixed/variable deal: The fixed flow ones are cheaper and, unless you are trying to get really precise volumes, will be adequate for most needs. I find it easier to just vary the dosed volume by adjusting the amount of time the pump is on per day. Even with the variable flow pumps you will need to buy a light timer, because these are continuous duty pumps. They will just keep spinning all day long even if you set them at the lowest rate, which you will probably not want to do.

Hope that's somewhat clear.

 

[Anonymous]

So you guys just use regular old appliance timers (digital I'm guessing) or something more "exact"?

 

[Anonymous]

So you guys just use regular old appliance timers (digital I'm guessing) or something more "exact"?

Regular old digital appliance timers with 1 minute precision are exact enough for our needs.