It will provide 3 main functions via 3 levels of control, the controller will log sensor readings, will control the parameters of the fish tank, will alert when the monitored variables go outside the 'normal' parameters.
The controller will measure temperature, PH and light initially, latter on I may measure additional environmental factors such as flow, ORP, conductivity, water level and dissolved oxygen (DO).
From the initial measurements it will control, monitor, log and report on the temperature and control the heater accordingly. Initially PH will be measure but as a means of warning only, eventually this may expand to control CO2 dosers. Light will be used to sense the ambient light and could for example turn the fish tank lights off earlier if the light level in the house is below a certain level, or turn them up if light is at a low level. Alternatively this could be used to control the intensity of the lights in the tank to follow the climate locally. Eventually dissolved oxygen reading will control the air pump and the flow meter can report on significant losses of pump power, either from air lock after feeding pump stops or blockages and control the heater and air pump accordingly.
Other features will include, 5 minute or adjustable pump and heater pauses for feeding cycles and control of an automated feeder. Control of the pump for cleaning, feeding and water changes. Control of the air pump, for cleaning, noise reduction and night time. Control of lights which will be replaced with high power RGB LEDs, these will follow lunar and solar patterns based on data from the web and can be manually controlled for ambiance. Also they will be programmed to simulate cloud cover and lightening.
Future feature possibilities, water level and auto top control. Also the ability to auto water change, pumping water out and simultaneously heating and filtering and pumping water back in (possibly using a temperature controlled sump and/or top tank and mains attached RO unit.
Control is a key aspect of the project, the device itself must be able to independently monitor and control parameters automatically, but also make it possible to manually control and interface with the device. This manual control and monitoring will be both remote, via a web interface and local using an LCD graphics display and keypad. Reading will be stored on a web server and also backed up locally on an SD card. If there are any network issues the device will revert to local backup only until a connection is re-established and at which point, the web data loss will be restored from the SD card. Via the web all aspect will be graphically viewable and can be controlled, there will also be an IP web cam for monitoring the tank (possibly pan tilt controlled). Via both the keypad and the web settings can be programmed and changed and will be stored both locally and on the web, should a problem occur with the devices memory.
Currently my shopping list comprises of the following, there are sill a few things I need.
Atlas scientific - pH-Stamp: AVR, PIC, Arduino, Parallax NEW V2.0 $20.00 + $10 postage.
3p-3p 12X Arduino 20cm Jumper Cable Shield EQUIV SENSOR (160575951979) $1.96 + $2.43
3mm Heat Shrink 2:1 - 5 meters £0.99
13MM HIGH QUALITY BLACK HEATSHRINK / heat shrink £1.00 + £0.79 postage
|XBee Shield - Sparkfun||WRL-09976||1||£16.95||£16.95|
|Arduino Stackable Header Kit||PRT-10007||2||£1.25||£2.50|
|830 point Breadboard||352||1||£3.99||£3.99|
|140 piece Jumper Wire Kit||312||1||£4.25||£4.25|
|Stripboard 95 x 127mm||STRIPBRD95127||1||£1.75||£1.75|
|Light Dependent Resistor||LDR||1||£0.60||£0.60|
|One Wire Digital Temperature Sensor - DS18B20||SEN-00245||1||£3.25||£3.25|
|XBee 2mW Chip Antenna - Series 2 (ZB)||XBEE2MWS2CA||1||£22.95||£22.95|
|Serial Graphic LCD 128x64 with Backlight||LCD-09351||1||£26.00||£26.00|
|Arduino MicroSD Shield||DEV-09802||1||£11.95||£11.95|