I do a gravel cleanup every couple of months, I just take off my filter inlet pipe and put the gravel cleaner hose into it and vacum away.
The water change sytem it just a made up unit from some cobbled together parts. I have it hooked into my home water system. Using regular plumbing taps I adjust the temperature and monitor it to be 82 degrees. I have an inline thermometer which is accurate. Then I use an electric shut off valve that is 120 volts. It is a valve commonly used in industry to turn water on and off to cool an injection die. It has a been running for at least 10 years and I think it cost about $15. I just have it plugged into a digital timer that you might use for turning the lights on and off in your house. When the timer turns on the water valve opens. I turn on the water long enough to give me 10 gallons 8 times a day. I have arrived at this by trial and error but t seems to keep everything stable. The overflow system is a siphon sytem that overflows at the right level, and just drains out into the flower gardens through the sidewall of the house.
