Help with automatic weir squeegee design

[Formulator]

I have an issue with my new standalone refugium weir clogging up and raising the water level to the point that my ATO is compensating and causing small salinity swings between cleaning. I want to build a simple squeegee system that will automatically clean the weir every few hours to prevent this problem.

The design I came up with is essentially just a linear 2” actuator connected perpendicularly to a squeegee that runs parallel to the weir. In resting position the squeegee sits below the weir, then at predefined intervals controlled by my apex, I need it to cycle up and down to clean the weir.

I’m not an electrician, though I understand the basics and can do some basic soldering. I can’t figure out what I would need as far as a relay or digital switch of some kind that will switch the polarity of the current going to the actuator motor when it gets a signal from my apex which would essentially just be an on or off remote signal. I’m thinking I would need two inputs - one to turn the motor on, and one to control the polarity. Or does apex have built in polarity control for DC motors?

Any suggestions are highly appreciated!

 

[Troylee]

I wouldn’t plan on it lasting too long that close to salt water… I’d be afraid of the rust and components contaminating my tank.

 

[Formulator]

I wouldn’t plan on it lasting too long that close to salt water… I’d be afraid of the rust and components contaminating my tank.

I found a waterproof one and it would be mounted above the tank. With the fuge being very low flow, splashing and salt creep is minimal. And hey, if it doesn’t work so be it. I’m only in for $40 in parts and its a fun project to me.

 

[AnomMatty]

Following along, because DIY.

Do you have a link or p/n for the actuator?

 

[Formulator]

Following along, because DIY.

Do you have a link or p/n for the actuator?

https://a.co/d/1m5JpGY

 

[Formulator]

Here is the design I have in mind. Obviously not to scale, but you get the idea...

 

[Formulator]

And regarding corrosion or pollutants, I found 100% silicone squeegee which would be the only water contact material.

 

[KStatefan]

I would try to eliminate the problem first. Why is it plugging up?

 

[yury88]

I like DIY and electronic, but stupid question - why do you even have weir after you refugium?
Just dump this and problem solved.

 

[Formulator]

I would try to eliminate the problem first. Why is it plugging up?

Detritus and algae. Its a refugium...

 

[Formulator]

I like DIY and electronic, but stupid question - why do you even have weir after you refugium?
Just dump this and problem solved.

To keep the chaeto where it belongs and not in the rest of my system wreaking havoc on my pumps/powerheads

 

[Formulator]

Look folks, I want to build this thing and I think its a neat solution. Can someone please help with suggestions on how to make it work rather than trying to talk me out of the entire idea?

 

[AnomMatty]

Working on the presumption the Apex power bar can provide the DC voltage to operate it, I think you can get by with something like this:
Switch

Not sure what your options to ground it are, and this might require 3 outputs.

 

[yury88]

To keep the chaeto where it belongs and not in the rest of my system wreaking havoc on my pumps/powerheads

So just 3D print better weir that will not have this problem.
Nowadays we have these 3D overflow weir with ridiculous performance.

In my case I just have a wall made of biomedia bricks just after refugium and have zero problem

 

[Troylee]

I’d love to help ya but I can’t figure out a good, safe way to do this Personally… maybe @Sisterlimonpot could help ya out he’s the gadget guru with building controllers and what not. I just fabricate.

 

[AnomMatty]

Working on the presumption the Apex power bar can provide the DC voltage to operate it, I think you can get by with something like this:
Switch

Not sure what your options to ground it are, and this might require 3 outputs.

What I'm envisioning is
Apex out to positive lug (On signal)
Top lugs out to actuator
Apex out to left small tab (yellow from switch) (Extend signal)
Apex out to right small tab (blue from switch) (Retract Signal)

Then it'd be a matter of figuring out it takes X seconds to extend, and Y seconds to retract, and getting the Apex to On + Extend Signal for X seconds, followed by On + Retract Signal for Y seconds, on whatever schedule you want.

 

[KStatefan]

Look folks, I want to build this thing and I think its a neat solution. Can someone please help with suggestions on how to make it work rather than trying to talk me out of the entire idea?

OK

I am out.

 

[Formulator]

To help folks visualize the weir, its purpose and the problem:

 

[yury88]

Ok, if you insist:
Idea with linear actuator with vertical mount is too complicated.

You can just use scraper with connected belt that will move on weir like on the linear rail.
Plastic gears to move belt are available on marketplace

 

[Formulator]

Ok, if you insist:
Idea with linear actuator with vertical mount is too complicated.

You can just use scraper with connected belt that will move on weir like on the linear rail.
Plastic gears to move belt are available on marketplace

I thought about this but thought the motor would be too close to the water for comfort and also means the scraper is covering some portion of the weir at all times, reducing flow.

Also, I am still stuck with the same problem of needing to switch directions of a dc motor at predefined interval, i.e the belt needs to push the scraper back and forth, not just one direction.

I don’t understand why my vertical mount is too complicated. I’m not asking for help mounting it. I need help with the electronics piece.