I have an idea wondering how well everyone thinks it could work
- Thread starter dr_sudz
- Start date
for sure there would be there would be check valves as stated before, I was thinking i would cap the top portion of the wiers but after thinking about it it should be alright to leave it open but maybe have some meshing on top to prevent fish from trying to swim down and in. I have heard that oxygination is reversed a fair amount when shot through the pumps so something to keep in mind. Water aggitation is the top goal for the gas exchange.
In a properly designed system, check valves are not needed. If you are planning on spring loaded check valves, you better go to Homey Depot and play with one first. If you are thinking of duck bill check valves, revisit Murphy's Law and think 'leakage' at the worse possible time.
The ones I am thinking of we used all the time when building ponds. basic ball and seal type when the water flows the into the tank the water flows around the ball, but when the flow is reversed due to power outage, the ball and seal stop flow and keep everything in place. I dont like springs in a check valve one more thing to fail.
dr_sudz;550967; said:
Trying to get a grasp on "oxygenation is reversed" part...can you elaberate?
And gas exchange takes place at the surface (air-water interface), unless you have air injection then it partially happens underwater. Surface tension needs to be broken, hense the need for falling water or air injection. Bio-wheels are also good for gas exchange.
How Does Mother Nature DO IT ALL, and still have time to look pretty!?!
Dr Joe
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I have been told that when the water passes through the impellers of the motor you loose the gasses that are trapped in the water so airating your sump wont do any good for your aqaurium.
HMM i smell an experiment here..
HMM i smell an experiment here..
Theoretically there's a little truth to that, but that is for a higher speed impellers that actually can compress the water in the pump housing. There's someone advertising that what your saying happens with bilge pumps used as aerators too...'course they sell a different style aerator kit (Hhmmm). Kinda like mixed medifores. Hey, they sell to fisherman...We buy stuff 'cause it's shiney 
. They never would susapect that we'd understand sumpthin'...
If you've got a dissolved oxygen meter can think of some other experiments to do to...
Dr Joe
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. They never would susapect that we'd understand sumpthin'...If you've got a dissolved oxygen meter can think of some other experiments to do to...
Dr Joe
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You know I am wondering if I am getting co2 reaction mixed up with the o2 reaction due to the fact that 02 is trying to enter the water while Co2 is being off gassed. Would that make sense that the water fall and impellor would disperse CO2 more then the O2 thing?
dr_sudz;550983; said:
I like the idea of the ball check valves. I have only seen them DIY and didn't know they were manufactured. My experience with spring check valves is that the spring is always too strong. In aquariums, our pumps just are not strong enough to open them and have any appreciable flow left over. Also, I have experienced seal failure in old check valves. This may occur as slow leakage but if an outage is over a long period, it may amount to more water on the floor than originally planned. I have had too many bad experiences with Murphy's Law (I hate Murphy), so I would rather design without check valves where practical.
Another thing is there are flapper check valves. Inside them is a rubber flap with a weight. They can be used vertically or horizontally. When the rubber gets old, they will leak too.
Duck Bill check valves are like air line check valves. When they operate in the open position over a long period, they stiffen into the shape that they are normally (open).
dr_sudz;551003; said:
You were told half the story of impeller (and propeller) cavitation. At high speeds and at gas saturation, the gas comes out of solution on the low pressure side of the impeller blades. What you were not told is that the gas bubbles return to solution when the pressure returns to normal. Keep in mind that the gas bubbles remain in a closed system in the pump.
In most pumps and under most conditions, cavitation does not occur. It is part of Pump Design 101 to allow plenty of fudge factor for cavitation. If the return to solution occures on the prop or impeller blade, it will cause mechanically induced corrosion.
