Hi Chris,
I obtain two different systems with four respectively three aqua-terraria. In the first of these set-ups four tanks are positioned one above the other and connected via a filtration circuit. The heart of this set-up is a canister filter which pumps water via an external heating unit into the upper tank, which is connected via two drilled outlets back to the lower tank and again to the lower and again to the lowest. The tidal effects can now be created using this outlet-arrangement. In the three upper tanks at a time one outlet is allways open, with the uppermost sited at highwater level and thus also preventing the accumulation of surface scum. The second outlet in each of the three upper tanks - lower down - is opend every 12 hours for a period of 6 hours via an electrically operated ball-valve connected to a time-switch. The most cost-effective method is to use a computer-controlled system intended for watering the garden that contains the ball-valve and time switch. Using this method alternating low and high tides are created reciprocally in two tanks at a time. However it is important to ensure that evaporated water is regulary replaced so that the canister filter doesn´t end up sucking in air as by virtue of the construction of the set-up the loss of water will be apparent only in the lowest tank.
The second set-up functions similar to yours. But I use two pumps, one stronger and one weaker. When the pump with the lower throughputs is in action for 6 hours, the water flows through the subsidiary, lower outlet and low tide occurs in each tank. By contrast when the stronger pump is in action for 6 hours, the lower outlet is inadequate to drain off the incoming water, hence the water level in the tank gradually rises until it reaches the overflow (high tide).
In both systems the water is not only filtered but heated in the low- as well as the high tide stage.
In 5 of these tanks I maintain and breed different species of fiddler crabs, other species of fiddler crabs I´m trying to breed, in 2 tanks I try to breed P.novemradiatus. Each Aqua-terrarium of the 4-tank-system extends over 1 squaremeter, each aqua-terrarium of the 3-tank-system is 110cm x 80cm x 40 cm.
I don´t understand your system with the two timers exactly. If I understand your set-up correctly, the first timer works for 23 hours and in this timer another is plugged in.
When the both start working together, there are 6 hours high tide (pump is working), 6 hours low tide (no pump), 6 hours high tide again (pump is working), and then 7 hours low tide, because the first timer doesn´t work for one hour. If this is correct, in a few days the high tide must be interrupted, because of the first timer. the pump can´t work. Or where is the mistake in my train of thought?
Hans-Georg