Overflow design to also allow for larger water changes, advice sought

[pedrofisk]

I am working on the design or my fish room plumbing system (more to come on the whole design) and I have a question on drilled aquarium overflows. I am looking to add overflows with the low profile strainer to 10g and 20g highs. My question concerns the desire to have the strainer assembly do double duty for larger water changes. Is there any reason to have the strainer assembly unglued to a bulkhead with a slip fitting on the inside so the assembly can be rotated to make larger water changes?

I have not found an example of anyone doing this which leads me to believe it will not be practical. The first thought is the danger of the assembly always slipping out of position or worse, out. However I am tempted to try it. Has anyone else given this a try or know of a good reason not to do it? I always believe in getting the best expert advice but also in trying something new.

Here is a very simple front and side elevation on a 20g tall of what I am talking about. The horizontal dashed line represents approximately 50% of the water line. Thanks in advance!

Edited August 13, 2020 by pedrofisk
spelling

[Andy's Fish Den]

I have seen in a video on YouTube someone drilled their tanks closer to the bottom and then had a long upright drain in the tank for normal use with the auto water change, then they could rotate the elbow and drain it down further if need be.

[Cory]

All of my tanks in my fish room and store are setup this way. Not really to do the larger water changes, mostly out of no reason to glue in the stand pipes. 
 

I don’t have a need for large water changes with an auto water change system. Rarely do I utilize the feature of being able to make them do larger water changes, only when I glued in my back grounds really. 

[pedrofisk]

2 hours ago, Cory said:

All of my tanks in my fish room and store are setup this way. Not really to do the larger water changes, mostly out of no reason to glue in the stand pipes. 
 

I don’t have a need for large water changes with an auto water change system. Rarely do I utilize the feature of being able to make them do larger water changes, only when I glued in my back grounds really. 

Thanks that is super helpful and solves several concerns. Water here is great but also metered and expensive so I don't want to water change by filling and letting the old/new mix overflow. Is there a term for that? I'll still be siphoning mostly but I figure why not build in the option if practical.

[Dean’s Fishroom]

I have a great idea for you but need a little time to get it legible.

[pedrofisk]

2 hours ago, Dean’s Fishroom said:

I have a great idea for you but need a little time to get it legible.

I would love that, thank you! Please take whatever time you need. I am also working on a rack design based on the wood rack you built in your room because I have such super limited space. It's actually the laundry room in fact with only room for 6' linear rack, a ceiling that is only 6'-10" and the most uneven concrete floor possible so the pre-fab shelves just won't work. I am going to start a thread on that this weekend.

[Dean’s Fishroom]

Okay so here you go. . . one hole in the tank at what you want to be the large water change level. The height of the top T and 90 is what sets the water level in the tank. Using the T makes it so that no siphon can be created, You could also probably use two 90's and drill a hole in the top for a siphon break. Auto drip type water change and the water overflows and goes down the drain. Note: the ball valve must be closed for this. Large water change, open the valve and the tank will drain down to the level of the bulkhead fitting. This keeps all that extra pipe and stuff out of sight and out of the tank. No need to reach in the tank and rotate a pipe, etc.

Pictures are just for the idea you would need to determine the actual lengths of pipe etc. Might need some trial and error on getting the water level set. But once you did one tank you should be able to do any others.

Hope that make sense. 

[Streetwise]

I have not tried any overflows, but I am interested in safe rainwater overflow for my tubs. Someone sent me this idea:

 

[Devlin Mc]

5 hours ago, Dean’s Fishroom said:

Okay so here you go. . . one hole in the tank at what you want to be the large water change level. The height of the top T and 90 is what sets the water level in the tank. Using the T makes it so that no siphon can be created, You could also probably use two 90's and drill a hole in the top for a siphon break. Auto drip type water change and the water overflows and goes down the drain. Note: the ball valve must be closed for this. Large water change, open the valve and the tank will drain down to the level of the bulkhead fitting. This keeps all that extra pipe and stuff out of sight and out of the tank. No need to reach in the tank and rotate a pipe, etc.

Pictures are just for the idea you would need to determine the actual lengths of pipe etc. Might need some trial and error on getting the water level set. But once you did one tank you should be able to do any others.

Hope that make sense. 

If I could absorb 5% of what goes on in your brain, Id be a brilliant man.  

[pedrofisk]

7 hours ago, Dean’s Fishroom said:

Okay so here you go. . . one hole in the tank at what you want to be the large water change level. The height of the top T and 90 is what sets the water level in the tank. Using the T makes it so that no siphon can be created, You could also probably use two 90's and drill a hole in the top for a siphon break. Auto drip type water change and the water overflows and goes down the drain. Note: the ball valve must be closed for this. Large water change, open the valve and the tank will drain down to the level of the bulkhead fitting. This keeps all that extra pipe and stuff out of sight and out of the tank. No need to reach in the tank and rotate a pipe, etc.

Pictures are just for the idea you would need to determine the actual lengths of pipe etc. Might need some trial and error on getting the water level set. But once you did one tank you should be able to do any others.

Hope that make sense.

Wow, that's a brilliant idea, I completely get the concept. It is like an over the rim overflow except it is out side the tank.

I think I will need to extend it so the valve is below the aquarium shelf but I don't think that changes the flow physics. I probably won't do drip water change, at least at first but this system still works either way. the water in I am designing can be setup to drip or converted later. Do you do anything on your overflows to protect for fry? I worry about it a little more with the strainer lower rather than at the water line.

I am going to get this mocked up and will post the testing. Thanks so much @Dean’s Fishroom!

[pedrofisk]

Almost have all the parts to proto-type @Dean’s Fishroom overflow design. Hopefully I can even get a video out by this time next week!