As I’ve started to think up Paludarium 2.0, more and more ideas are popping up. The most recent one: How to build the water household. With all the things I want, and all the technology I can build, I am now thinking up the specs and features I need/want, and how I can build them so that it will actually work, and most important, KEEP working.
Specs for the flow of water
I have quite an extensive must have / wanna have list. Here they are in random order:
- An external aquarium filter should filter the water 24/7;
- A Fast streaming, low waterfall in Paludarium 2.0 so that there will be a current inside;
- Being refresh water using a tuneable mixture of tapwater and reverse osmosis water electronically;
- Being able to use a mist maker that works on pure reverse-osmosis water;
- Being able to add pure reverse osmosis water to counter evaporation;
- Being able to measure when the waterline is at its maximum;
- Measuring and heating the water outside of the Paludarium 2.0.
Quite a list. Below is how I plan to build these features so that they work, are simple and keep working:
1: Using an external aquarium filter that filters the water 24/7
Using an external aquarium filter is the easiest way to create a decent filtering mechanism. I somehow need to draw water from the tank, filter it, and inject it back into the tank. To be able to do this, I will have two holes drilled in the glass in the back just above the waterline. I will mount pipes through these holes. One pipe will draw water from the main tank, the other will inject it back.
2: A Fast streaming, low waterfall
As the water will not be need to be pumped up a great deal by the external filter, I can use the water that is injected back as the waterfall. This will mean I have to be careful in choosing the filter pump; it should displace enough water for the waterfall to work as expected. I currently have an Eheim 2222:
This unit displaces around 500 litres per hour, which comes to 135 mL each second. This may not be enough, so possibly I’ll be upgrading to a larger filter pump that will perform at 900 or even 1500 litres per hour.
3: Automatic water refresh using a mixture of tapwater and reverse osmosis water
Since in the new Paludarium 2.0 I will have the luxury of having tapwater available, as well as a drainage, I want to be able to automate the water refreshes. I want to refill the paludarium with a tuneable mixture of tap water and reverse osmosis water.
To be able to electronically start and stop the flow of water, I will need to implement one or more solenoid valves:
In this case I have chosen to use two solenoid valves: One will switch on/off the tapwater injected directly into the waterfall, the other will switch on the water flow to a reverse osmosis appliance which will inject its water into the waterfall, but in a special compartment where also the mist maker will sit.
4: Using a Mistmaker with pure reverse osmosis water
A mistmaker is very effective in raising the relative humidity inside the paludarium. A typical unit looks something like this:
Because the mistmaker sits in its own compartment where reverse osmosis water flows directly into, the mistmaker will always output pure water. Any excess water in this compartment will overflow the apartment into the waterfall.
This setup allows me to have pure reverse osmosis water for the mist maker, while at the same time I can mix the reverse osmosis water directly into the water flow of the waterfall (see 3: ).
5: Counter evaporation with reverse osmosis water
Evaporation can be quite intense in a paludarium. Multiple liters per day may evaporate! I want to be able to counter evaporation with pure osmosis water. This is because as the water evaporates, only pure water evaporates, while all minerals and other chemicals remain. So it makes sense to replenish this with pure water as well, so I want to use pure reverse osmosis water for this.
As the two water streams I can inject (tap water and reverse osmosis water) each have a separate solenoid valve, I can also choose in inject only reverse osmosis water. Another tick in the box!
6: Measuring the height of the water
I have been thinking on how to measure reliably what the water level is. This is hard to do, especially hard to make it simple and reliable. In the end I came up with a very simple yet very effective way: I am really only interested in knowing the water height is at its maximum. So what I will build is the simplest of all: I insert a flow meter in the drain!
When for example I counter for water evaporation (see 5: ), I want to know when to stop adding reverse osmosis water. This is really simple when I have a flow meter in the drainage: As soon as the flow meter start running, the water level is at it maximum (and overflowing!).
Another upshot is, that I can very effectively measure how many liters I have inserted during an automated water refresh (see 3: ). The amount of water that flows out of the drain is very close to the amount of water injected!
7: Measuring water temperature and heating the water outside of the plaudarium
Heating the water outside of the paludarium is done by using an external heater. These heaters are inserted into a filter line like this one:
This heater has an thermostat included; it measures the temperature of the incoming water, and switches on or off as required.
My idea is to use this type of heater, and set it to 29 degrees. I then measure the water temperature myself electronically, and switch the heater on and off electronically. This way I can regulate the temperature myself, and in case something goes wrong my paludarium will not get fried 🙂
A picture syas a thousand words
So given all the requirements above, I have drawn a logical diagram how things should look like:
You can click the image to get a larger version. Remember, this is version 1.0! I may need/want to change things, but as it looks now this setup will fulfill the requirements: simple, must work, must keep working.
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