liquid carbon dosed via a persistaltic pump?

[a1Matt]

I am contemplating auto dosing liquid carbon with a peristaltic pump, but the evil smell of the carbon tells me it is not sensible to leave it in an open container. So...

Can a persistaltic pump be fed from a container that is sealed closed?

I have not tried, but logic tells me that it will not work.
Maybe there is a bottle design out there with some kind of one way valve\diaghram in it that that gets around this potential problem?
Any ideas on what these would be called to help me search the web?


For those curious...
I tried autodosing with an allinone solution before, but the ph of my tank was too high and the ferts precipitated and gave me cloudy water.
I now have two pumps sitting waiting for me to set up macro and micro solutions with, andam aiming to do this over the xmas break.
I would like to also autodose carbon to assist keeping stable CO2 levels, thus helping to prevent inducing (more) BBA into my tank.

 

[Tony Swinney]

Sounds like a good plan to me Matt (and one I might follow too )

Sorry I cant help with a bottle design. I wonder if a sealed bottle, but with a valve made of CO2 tubing and incorporating a non return valve would do the job ? Would the pressure in the bottle be enough to open the non return valve ???

Tony

 

[a1Matt]

I'd not thought of DIY'ing the valve. That might well turn out to be just the help needed with the bottle design

10min of research via google brings up a tutorial on check valves which states 'There are a number of reasons for using check valves, which include: .... Relief of vacuum conditions' ( http://www.spiraxsarco.com/resources/st ... valves.asp )

bingo!

It should be easy enough to rig something up with stuff I have lying around already so I've nothing to lose in trying it out.
I'll feed back here (within a couple of weeks at a guess) how I get on.

Keep the ideas coming people!

(Jeez! look how many valve types there are .... http://www.valvedirectory.com/valve_glossary.html think I will be getting my head around 'air' and 'vacuum' next, I already know what 'check' is!).

 

[squiggley]

What about a bladder type bottle. The type similar to the iv drip in hospital where the bag collapses at liquid is expelled.

 

[CeeJay]

Hi a1Matt.
I understand the reason behind your thinking. I can't stand the smell of the stuff either .
But I would be inclined to keep it simple. Why not undo the lid a quarter turn? As long as air can get in you will be fine and most of the smell will be retained within the container.
A little test you can do for yourself is this:-
1. Tighten the lid on your liquid carbon bottle
2. Lightly squeeze the sides of the bottle and undo lid slowly
3. When the sides of the bottle start to go inwards you have now broken the seal.
That's all you need to do

Now if your lid is at the bottom of your dosing container, I'll shut up because it will leak all over the floor .

The amount of vapour released will be miniscule as it is not pressurised. But if your still concerned, then it's back to the drawing board I'm afraid.
Just an idea.

Chris

 

[a1Matt]

What about a bladder type bottle. The type similar to the iv drip in hospital where the bag collapses at liquid is expelled.

Yep, that sounds like it would work

I just googled 'bladder valve' and definitely got more than I bargained for!
I could really have done without the picture results in particular

@Chris - I could well be overcomplicating things, overthinking is one of my traits . I will try your idea as well

I'm liking the feedback from you guys, it is really helpful

 

[YzemaN]

I just used a 2L water bottle. I drilled a 5mm hole in the cap for the 4/6mm tube that feeds the pump and next to it I drilled a 1mm hole to let a bit of air in without too much evaporation...