The Reef Tank banner

1 - 6 of 6 Posts

·
Registered
Joined
·
297 Posts
Discussion Starter · #1 ·
Recently I came across a hydrometer that can stay in he tank full time as long as it was submerged at 6cm (I think, may have been as high as 8cm). I start thinking how could you make a digital Hydromter or did such an item exist and is there a damand for such a item.

Well if you are really into details then a digital hydromter could be used a few different ways such as an alarm, some kind of auto mixer or if you are really into details, simulating seasons on or topgraphy such as fresh water runoff to a lagoon.

So how would you build it? I use to use a notebook computer and a peice of software to count the lap times of a r/c car called a Mini Z 1/28th scale that we used a simple $2.00 laser and a $1.79 optic sensor IR receiver and a peice of tape at differnt height son the antanna. the optic receiver came from radio shack and was attached as a switch attached to the parrallel port for the six pins that control items such as paper out, form feed, online ect etc etc and all that other tech'e suff....... any way here is what I am thinking if you had a settling tank with a black tube, use the old school glass hydromter. now either using the IR emitter an receivers or a laser. There has to be a way to bounce the light off of the hydromter with-out adding weight to the unit (if you add or remove weight the hydrometer would have to recalibrated and being that it is sealed in glass, well you get the picture)

I was thinking of using a distance meter such as one of these home depot laser ruller to measure the vertical distance of the hydromter. or take a stud finder and turn it sideways so it reads the top of the glass hydromter.

the next step would be, How to get that information back to a serial port or some kind of control device.

so in a nut shell I beleive it is possible to make such a critter but is it worth it. So far the parts to track it optically would run about $6.00 the black tube and glass hydrometer about $8.00 and the control unit could be the pc you are reading this post on. a standard parralel port will give you 6 pins that can either be open or closed so 1.021, 1.022, 1.023, 1.024, and he 6th for the water level sensor.

Now this may be a bunch of fantasy babble or hopefully it may inspire someone to give it a try and if you do, Don't forget to take pictures and lots of notes when you build it. I if you make a few million of it, wel I have had the same email address for the past 4 years and plan to keep it a while longer, plus the fact I have the sourcecode to read the parrallel port to save you some time.
:lol:
 

·
Registered
Joined
·
1,019 Posts
I am not convinced it would be worth it. If you are talking about hooking up a digital display, or some sort of digital readout I am sure it can be done. But you are still talking about a swing arm hydrometer, so just making the display digital does not increase the precision or the accuracy of the measurement. And I would think that a submerged swing arm hydrometer would be less reliable than one that is used intermittently and cleaned with ro/di in between readings.

Digital salinity monitors are available and might be useful for what you want. But a hydrometer and a salinity monitor do not exactly measure the same thing. The high alkalinity of our tanks "fools" the salinity monitors to some extent and cause them to read in accurately compared to refractometers, the gold standard.
 

·
Registered
Joined
·
297 Posts
Discussion Starter · #5 ·
you could also think of it as an alarm. basic binary 0 or 1 .. if it is set to 1 when the tank is optimal then anthing else would be 0 and send an alert via however you wanted, SMS, email, Screen blinking, Sound file "YOU GRAVITY LEVEL HAS DROPPED DUE TO WATER LEVEL LOWER OOVER THE PAST 2 HOURS" I love A.I..

read this below figured out the sensors


Take a older notbook with win98 or win 2k . use Winbatch to monitor the paper feed and the paper out..

shoot the laser across the tube just above the glass hydrometer this is set to close circute mode.


set the other just below the top of the glass hydrometer. if the hydrometer rises it opens the top circuit if it drop then it closes the second circuit this giving you an idea weather the gravity has risen or lowered.

The IR relays are a $1.59 each at rasio shack take the two of the $2.00 laser pointers from the flea market. use a peice of schedule 40 pvc pipe

Drill holes in the bottom to let flow through mount . mark the range from the hydrometer then mount the lasers ans IR's and coat it in non toxic silicon.you will have to do a little soldering to run some wire to the parl. port and to the 3v dc power supply.

Download Winbatch (Its free from wilsonware, www.winbatch.com without the compiler) you have to pay for the EXE compiler but you can run the script in the studio editor just like old school BASIC.

Open the parl. port and capture the port staus every 10 seconds average it over 5 minutes (you want some play in case somehting is splashing around.

If the average for circiut 1 is greater then 15 then it has been closed for more then half the time. if it is under 15 then is has been open for most of the time at this point use the K-mail extender and send yourself a SMS message to your cell phone.

Do the same for the lower sensor except it is open for most of the time. Once you have the script written send it to me and I will compile it into an EXE.

This I will try to build this this weekend. I also have a Mini Mill machine. what metal can I get away in using to make mounts and parts I was thinking aluminum and coating it with silicon very well.
 

·
Registered
Joined
·
297 Posts
Discussion Starter · #6 ·
Crappy2D layout for digital Hydrometer

Here is a crappy layout of what I am talking about. will post the winbatch script as soon as I find what extenders I ned to use.
 
1 - 6 of 6 Posts
Top