Backyard Aquaponics
A place to discuss aquaponics

I'm building some level controls and I'd like some suggestions for options on the board. My thought is to make it multipurpose.

Here are the things I'm thinking of:

1. 2 channels.

2. Can be used just to sense levels and switch relays.
a. Can be used to turn on air pump if power fails or if water level is low.
b. Can also interrupt a pump if level is low(in case of broken pipe).
c. Can be connected to an alarm.

3. Can be used as a sump contoller (start pump on high level, shut off at low level).
I suppose an alarm could also be added if high level isn't seen after x minutes.

Any other ideas? All input is welcome!

Perhaps a timed flow sensor, if no flow after a given period the pump shuts off and the back up aireation device is turned on as well as an alarm.
Used on the grow bed return to the tank, if the grow bed does not empty due too clogging and what not.

You know I like the idea of the sump controller.

I of course also like the control that can sense low water and shut off pump and switch to air and also on loss of power switch to backup power air.

Other options I think might be of interest. Temp or DO sensor that could switch on air if the DO got too low or when the temps get too high. Temp logging would also be of interest to me.

The temp thing I'm doing on my other board. DO I think is just WAY too expensive. I'll have to do a little studying to see how to actually sense it.

For the DO Might just be a good idea to have a little knowledge of it so if some one wants to pay to buy the sensor, you can do up a board to hook to it and control what it needs to.

The temp monitoring would be something interesting to have logged to know the max and min temps during the hottest and coldest parts of the year.

Oh, and the temp sensor would be handy when/if any of us get solar heating/radiant cooling hooked up.

Yep that's what I'm going to do. I monitor the temp in my fish tanks and the greenhouse. I use the one in the greenhouse slow my pump cylcle if it gets too cold and the one in the FT turns on a small heater if it gets too cold. Hopefully by next winter, I'll have the whole solar thing going.

I have a ridiculous idea for sensing low DO ... detect fish near surface (at non-feeding times).

This is really easy, any infrared LED/detector proximity sensor (cheap and simple).

There may be false alarms but it is not bad to pump air for no reason. Simultaneous temperature reading may help in judgement. Also a button may be provided to indicate feeding time so that this 'crazy' low DO sensor may be disabled for a short while.
This is suitable for use with a microcontroller. A discrete logic chips based circuit may also be designed with a little brain workout.

I've had this idea in my head for quite a fair while but I put off telling all of you about it because I thought it would be unreliable and silly.

But after a long while, and since the topic of DO sensors came up again, I decided to tell you because I couldn't improve my idea any more and thought any of you could try. Or atleast do something with the idea and have fun (I don't need it - I have a low stocking density).
This is really cheap you know even if you don't compare it with expensive real DO sensors.

The second of my two posts above is rant-ish and may be totally skipped without loss of continuity/information.

Guys,, It's the sensor that is the expensive bit.

I keep an eye out on ebay ,, missed one last month that sold for $100 ( AUD ) , also in our systems we are not using expensive pure oxygen , so you would only need to check DO levels maybe twice a year ,, once you know your levels are correct , they should stay stable.

Gokul , switching an air-pump on and off like that would work ,, but probably be just as cheap to leave the pump on full time.

Gokul I don't think your idea is too silly. I once wondered if you could estimate the weight/size of fish by hooking up a web cam and doing some image analysis if they were to swim in front of a white board or other. Take the pixel area of their silhouette to estimate volume and mass.

How about a tilapia stripe counter, for detecting when they are stressed?

The detector at the top surface could double as a dead fish detector.

There are demand feeders already for feeding them when they think they are hungry. The fish bump a rod that moves a shutter to let food fall out of the feeder.

Gokul I don't think that's such a bad idea either. It just depends on how much automation you want. As for me, I like to put controls on everything .

This particular post is more gear to being able to sense the level of water. I have a design that senses water with two wire probes and that's what I'm trying to get ideas for.

I will put some thought into your idea though. thanks.

Gokul I forgot to say that there are almost NO bad ideas. Thinking outside the box is how we get better. Maybe an new idea doesn't work for everyone but there may be someone out there that will really benefit. Don't stop thinking and don't stop posting your ideas.

No I won't stop posting my ideas no matter how silly they appear don't worry!

I already use such a thing in my system! (I made it myself and it mainly has only a 555 IC, two resistors, probes, a relay. This is my pump controller / timer.)