I haven't seen any posts on this site about the style of auto top off I used for my aquarium so here is how I made mine. This design uses a sealed container with two tubes, one for siphoning fresh water from the container into the aquarium and one for triggering the siphon to operate when the water level in the aquarium drops.
Items needed:
- 13/64 inch drill bit and drill
- 2 various lengths of 1/4 inch RO tubing
- Glass container
- Rubber stopper
- Vegetable oil
For my container I used a 4 liter bottle of Carlo Rosii sangria from Walmart, pro tip don't attempt to drink the entire bottle of sangria in one night. The size of the stopper will depend on the size of the opening on whatever container you use. For my application I used a #6 medium rubber stopper made by The Hillman Group which I found at Lowe's. I am not sure about the possibility of the rubber stopper leaching something into the water but because it wont be in contact with the water I am not too concerned about that.
Step 1
Start by drilling two holes in the stopper with the 13/64 inch drill bit. While drilling push the drill bit back and forth a few times from both sides to make sure the holes are smooth.
Step 2
Use a tooth pick to apply a small amount of vegetable oil to the inside of the holes in the rubber stopper, this will help with inserting the RO tubing in the next step.
Step 3
Shove the RO tubing through the holes in the rubber stopper in the direction of decreasing diameter. The tube circled in yellow only needs to be pushed through about in inch or two because this should not come in contact with the water inside the container. The tube circled in black should go all the way to the bottom of your container. If you are using kalkwasser in your auto top off then you can adjust this tube to be a few inches above the bottom to avoid sucking up the kalk slurry that settles to the bottom.
Step 4
Place the container somewhere above the aquarium and stick the other ends of the RO tubing into the aquarium. You will need to trim the RO tubing so that the one circled in yellow sits just below the surface, this can later be moved up or down to set the water level. Cut the tube circled in black so that it sits a few inches below the surface of the water. These tubes sitting in the aquarium need to be secured so that they are not accidentally moved.
Step 5
Fill your container with RODI water put the rubber stopper in making sure to get a tight seal.
Take the tube circled in yellow out of the aquarium and blow in it to start the siphon then put it back in the water, this is the tube that sets your water level. As the water level drops below this tube air is allowed to enter the container and freshwater is siphoned into the aquarium. Once the water level in the aquarium reaches this tube air will no longer enter the container and the siphon will be paused.
This style of auto top off can be made relatively cheaply and has no moving parts to wear out but there are some drawbacks. You need to be able to store your auto top off reservoir above the aquarium. Also if the container is not completely sealed and air is allowed to enter then the siphon will not stop until your container is empty. This also means that the tube that sets the water level in the aquarium must be properly secured so that it is not accidentally moved by either yourself or any tank inhabitants.
Items needed:
- 13/64 inch drill bit and drill
- 2 various lengths of 1/4 inch RO tubing
- Glass container
- Rubber stopper
- Vegetable oil
For my container I used a 4 liter bottle of Carlo Rosii sangria from Walmart, pro tip don't attempt to drink the entire bottle of sangria in one night. The size of the stopper will depend on the size of the opening on whatever container you use. For my application I used a #6 medium rubber stopper made by The Hillman Group which I found at Lowe's. I am not sure about the possibility of the rubber stopper leaching something into the water but because it wont be in contact with the water I am not too concerned about that.
Step 1
Start by drilling two holes in the stopper with the 13/64 inch drill bit. While drilling push the drill bit back and forth a few times from both sides to make sure the holes are smooth.
Step 2
Use a tooth pick to apply a small amount of vegetable oil to the inside of the holes in the rubber stopper, this will help with inserting the RO tubing in the next step.
Step 3
Shove the RO tubing through the holes in the rubber stopper in the direction of decreasing diameter. The tube circled in yellow only needs to be pushed through about in inch or two because this should not come in contact with the water inside the container. The tube circled in black should go all the way to the bottom of your container. If you are using kalkwasser in your auto top off then you can adjust this tube to be a few inches above the bottom to avoid sucking up the kalk slurry that settles to the bottom.
Step 4
Place the container somewhere above the aquarium and stick the other ends of the RO tubing into the aquarium. You will need to trim the RO tubing so that the one circled in yellow sits just below the surface, this can later be moved up or down to set the water level. Cut the tube circled in black so that it sits a few inches below the surface of the water. These tubes sitting in the aquarium need to be secured so that they are not accidentally moved.
Step 5
Fill your container with RODI water put the rubber stopper in making sure to get a tight seal.
Take the tube circled in yellow out of the aquarium and blow in it to start the siphon then put it back in the water, this is the tube that sets your water level. As the water level drops below this tube air is allowed to enter the container and freshwater is siphoned into the aquarium. Once the water level in the aquarium reaches this tube air will no longer enter the container and the siphon will be paused.
This style of auto top off can be made relatively cheaply and has no moving parts to wear out but there are some drawbacks. You need to be able to store your auto top off reservoir above the aquarium. Also if the container is not completely sealed and air is allowed to enter then the siphon will not stop until your container is empty. This also means that the tube that sets the water level in the aquarium must be properly secured so that it is not accidentally moved by either yourself or any tank inhabitants.