Auto Aquarium pump shut off

Discussion in 'The Projects Forum' started by metaldav2005, Jul 26, 2011.

  1. metaldav2005

    Thread Starter Member

    Nov 21, 2009
    11
    0
    I have a issue I was wanting to put out there. I have a 100 gal saltwater aquarium with a sump underneath. I woke up this morning to find my siphon pump had failed and my main water pump was running dry:eek:. I would like to make an auto pump shut-off and basically I want to interupt the AC power to the pump when the water level reaches a certain point. I have a float valve that works, I haven't had a chance to put a meter on it but I believe it works on the principle of high resistance closed, low resistance when open. Any thoughts of doing this safely?
     
  2. Wendy

    Moderator

    Mar 24, 2008
    20,765
    2,535
    Welcome to AAC!

    Use low voltages with a relay for the AC portion. You can also use a SSR (solid state relay) to keep the currents down.

    You can also use a bare wire sensor to detect water. A float sensor will work just fine, but I would go with simplicity on this.

    How much electrical/electronics experience do you have?

    Another gentleman had a similar (but different) problem that he approached differently.

    Relay/timer design help
     
  3. BMorse

    Senior Member

    Sep 26, 2009
    2,675
    234
  4. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
  5. Wendy

    Moderator

    Mar 24, 2008
    20,765
    2,535
    OK, this is the fill system, similar to the link I showed. You are wanting something if it overflows, correct?
     
  6. metaldav2005

    Thread Starter Member

    Nov 21, 2009
    11
    0
    I have an auto top off system. The problem was up in the main display tank, there is a assembly called a siphon overflow box. This overflow must maintain a constant siphon that supplies water for the main filtration under the tank. The amount of water going down to the sump is equal to the volume of water being pumped back up to the tank. The siphon pump up on this over flow assembly somehow stopped maintaing the siphon and it starved the filter below. Thank the Lord if don't have the top-off system installed right now or it would have over-filled the main tank and my living room.
     
  7. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
    I've got the same setup.. However I simply drilled a hole in the top of the overflow box (weir style) and added a barbed fitting/air tube that gets routed to my powerhead.. So any air that gets trapped (or allowed) in the top of the overflow gets pulled out by the venturi head on the powerhead. Plain and simple..never fails..never loosed siphon.
    There is also the Tom aqualifter pumps that you can attach to your overflow to prevent that too if you don't have a powerhead w/venturi.

    Having said that.. a properly designed/sized overflow should NEVER loose a siphon. The only time I get air into it is when a snail sits on the edge of the overflow causing air bubbles. But if I would have made the weir a little deeper the bubbles would float up before the siphon part and never make their way into the siphon.

    Best solution is to drill the back of your tank to remove the over the edge type overflow. I wish I would have done that.. My sump was an after thought and it was too late to drill.
     
  8. metaldav2005

    Thread Starter Member

    Nov 21, 2009
    11
    0
    I have a AquaLifter pump on there now. I just got home and found the reason for the siphon fail. The hole where I have the AquaLifter pump hose installed is letting air in the overflow box plus the AquaLifter pump is not doing it's job:mad:! Fixed that. I was just worried of this happening again while on vacation or something and somehow stopping the main sump pump from running dry.
     
Loading...