Continuous feeding NPS filter feeders

[herring_fish]

Has anyone actually run into this problem?

My intent is to simply have a bigger peristaltic pump for the water rinse than for the food. I don't know for sure that this will work. I have just assumed that it would. Please give me your thoughts on this. Perhaps I have over looked something.

The water pump uses a bigger diameter tube and the motor is bigger so when the smaller motors run, the back pressure should not affect the upstream pumps. I will just have several "T"s in a row after the water pump and then go to the tank from there. The smaller diameter feeder tubes will flow into the bigger, water pump to tank tubing.

The way that I figure it, the very low flow food pumps will not produce much pressure. I will keep the tubes from the food pumps to the "T"s short, inside the refrigerator. The water pump can be outside the fridge. When the water pump turns on, I am hoping that the circuit (if you will) will see the lowest path of resistance after the "T"s . Hopefully, everything will flow toward the tank and not back up any of the feeder tubes and of course not back up to the water pump when the feeders turn on.

 

[slapshot]

If I understand what you are saying it would work but you need a one way valve after the peristalliic pump. The tubes do rupture. If that happened you would have a leak. If you are just dumping it into the tank it should work. I'm not sure I get what you are trying to do. Feed then wash the line out?

 

[herring_fish]

....In my old design, I have two tubes going to the moving carriage. This idea allows me to just use one.....

Further back in the thread, on 06/08/2011, I created post 206 that this came from.
I want to pump a few different foods to the 6 foot, 6 inch diameter plankton towers (but this could just as well be to a display tank). I would hope that the lowest resistance would be at the open end and not back up the smaller, more viscous feeding tubes.
The smaller pumps would simply deposit food into the bigger tube and the water pump would wash it out right after the other pump(s) shut down. For example, I might pump 1 to 5ml(s) of phyto paste into the tube and 1 to 3ml(s) of something else. Then I would wash it with a quart of water. I would do this every 3 hours.
I use 1 quart because that is the amount that I need to pump into the plankton tower to change 2 gallons out of 7 every day in order to harvest the plankton.
I would do this for each tower( 1 to 6 of them), every three hours so there might be only a few minute rest(5 to 8) before moving on to the next tower. That is way all the automation.

 

[aussiedan]

http://www.spaparts.com.au/products/Mazzei-Venturi-Injector-884K-3%7B47%7D4%22-Barbed.html

Is this a suitable venturi or do you need to go to the more expensive black model?
http://www.spaparts.com.au/products/Mazzei-Venturi-Ozone-Injector-978K-1%22-threaded-%252d-Kynar.html

 

[slapshot]

The cheap one is fine.

 

[Wave Ace]

http://www.spaparts.com.au/products/Mazzei-Venturi-Injector-884K-3%7B47%7D4%22-Barbed.html

Is this a suitable venturi or do you need to go to the more expensive black model?
http://www.spaparts.com.au/products/Mazzei-Venturi-Ozone-Injector-978K-1%22-threaded-%252d-Kynar.html

Have you got ebay ?

as in the UK you can get them for £30

 

[Aquabacs]

If you have access to the venturi injectors made by Kent, it is a far more cost effective solution.




Mike

 

[aussiedan]

Thanks guys, I've purchased on of the white Mazzei venturi's for the automatic feeding setup.

This is the main component, I even managed to find a fridge with 4 xpre-drilled 6mm holes on each side wall which is the right size for standard aquarium airline tubing. I've not completed any plumbing plans at this stage but will likely run the pipework loop on the external side wall of the fridge so there is only a very small (1cm or less) of non refrigerated line to worry about.

 

[herring_fish]

Very nice! Is that a converted Red Bull fridge that you bought from another reef hobbyist?

This brings me to one of my mistakes and questions. I wanted a glass front a few years ago so I bought a glass front, black beverage cooler. I didn't notice that they only go into the 40's or 50's, not 33 or 34 degrees. I set it aside because I wasn't ready for it yet but now, I am planning to buy a mini-fridge replacement thermostat to replace the one that I have in the cooler.

I have been warned that many of these coolers and fridges are built right to the minimum edge. The unit that I have may be so inefficient that a thermostat my not help. If it does, my bill might me too high. Looking at the construction of the non-glass wall, they look to be the same as a regular fridge in construction and thickness. The compressor is the same and a dorm fridge so I am going to try putting good money after bad.

That is, unless someone that has experience with this talks me out of it. Please ....save me from myself!

 

[aussiedan]

the fridge is actually branded as a coffee fridge (or milk bar) and made so that milk bottles can be kept inside and automatic coffee machines can use milk as required by being pumped from the fridge directly. It is a proper refrigerator and has a compressor and refrigerant inside.

I am still looking at the temps it can achieve and with my very inaccurate thermometer I am getting it to around 5-6 deg Celsius (very low 40's in Fahrenheit) which will hopefully be sufficient..

 

[herring_fish]

Has anyone actually run into this problem?

My intent is to simply have a bigger peristaltic pump for the water rinse than for the food. I don't know for sure that this will work. I have just assumed that it would. Please give me your thoughts on this. Perhaps I have over looked something.

We have been talking about back flow valves, venturi valves, hydrogen sulfide and refrigerators. Before we move on, I would like to know if anyone has actually had this back flow problem that is so bad that it breaks the tubing in the peristaltic pumps.

Again, I don't know because I haven't tested this plan but no one has answered back with experience on this that speaks to the contrary. Failing that, I would like to hear the logic that others may have surrounding this plan.

The water pump can be outside the fridge and the food pumps would be inside, very close to the food containers. Food would be flushed at lease every 3 ours.

I would think that if I pump competitively clean tank water into a bigger diameter tube "¦water will not run back up a smaller tubes that are full of thick phyto concentrate. I think that it will simply go in the path of least resistance.

Guys and Gals, do you see problems with this?

 

[herring_fish]

Last night, I was on another thread and saw this, re-posted from still another thread that I had seen before.This was on of my inspirations. I don't want the main collector/through, tube to be as big as in the picture because I am afraid that there won't be enough water motion to flush out the thick food but this is the idea. The system about has been working well for quite a while.

reefervet suggests that you use a venturi and he is one of the best NPS guys out there. I think that he has it on his return line so there should be more flow than what I want to do. I don't know what would happen in a lower flow injection. Also, if you use three or four foods, do you need three of four venturi.

This fridge is the Avanti SHP1701B 1.7 cubic foot refrigerator. The system has been proven to consistently hold temperature at 38 degrees with the refrigerator having the pass through pipe holes through it.

Different quote:

Also what it the temp reading inside the refrigerator? Might also recommend keeping a thermometer inside the unit as well, check it every so often daily, to see how stable the temperature stays in the main area the food is being dosed from. Main area should be around 38 degrees. Monitor the area where the peristaltic dosing pump is to make sure it doesnt freeze up.

I bought a Haier HBCN02EBB 1-4/5-Cubic-Foot 42-Can Flat-Black Glass Front Beverage Center and as I said, I plan to change the thermostat.

 

[aussiedan]

for the fridge plumbing, i can see all the connectors and john guest fittings but are you using actual john guest tubing or is it just the more rigid walled airline tubing?

I've got some JG elbows lying around and when I use the rigid airline tube it fits however if I use excessive force it will slowly slip out of the fitting where as with the JG tubing it is rock solid. I am hoping to use the airline as it is clear so I can see how the lines are doing.

 

[slapshot]

I use the tubing you can buy for R/O filters. It's a little thicker and more ridged then the 1/4 inch tubing we use for air lines.

 

[aussiedan]

I am after some advice about the Venturi system, I have hooked mine up (see photo) which is tee'd from the 3000lt/hr return pump however I can't seem to get any suction through it and rather is seems to slowly drip from the intake line :mad2: I have tried to have a look at it and it seems to have a spring loaded seat or something in the actual venturi which may not be sealing correctly causing the leak??? Any advice would be much appreciated.

 

[slapshot]

Assuming you put it in the right diection, it needs more flow then.

 

[Wave Ace]

I am after some advice about the Venturi system, I have hooked mine up (see photo) which is tee'd from the 3000lt/hr return pump however I can't seem to get any suction through it and rather is seems to slowly drip from the intake line :mad2: I have tried to have a look at it and it seems to have a spring loaded seat or something in the actual venturi which may not be sealing correctly causing the leak??? Any advice would be much appreciated.

Its a non return valve in the intake it could be stuck just jive it a push if it moved in then its OK if that dont work you may need more flow

 

[aussiedan]

Thanks for the replies. The Non return valve does move and bounces back but a very slow amount of water still drips through it when it is in the closed position..

What sort of flow rates are required, had trouble finding this data? With the 3000lt pump and all its flow directed through the venturi it is just under 800gph which i thought would be enough :crazy1:

 

[Wave Ace]

what size venturi is it ?

what size pipe and length have you got to / from it

you can work out the flow rate you have by timing how quickly the outlet fills a 1litre jug

 

[aussiedan]

http://www.spaparts.com.au/products/Mazzei-Venturi-Injector-884K-3%7B47%7D4%22-Barbed.html

this is the part I have, unfortunately I do have about 60 - 80cm of line each side of the venturi just due to the location of the fridge. I plumbed both lines into the return line for the tank so it isn't so easy to do the jug experiment but I think I might have to pull it all apart anyway by the looks of it :debi: The tubing is 19mm ribbed (smooth on inside walls).