a) How large is my pond?
The answer is easy for fish tanks, which is length depth # height = volume. For a pond it's not so easy, because of its crooked shape. A proved method is, to measure the surface and multiply it with half of the deepest point. For example: your pond is 3 m long and 2 m wide with a maximum depth of 1 m, so calculation is: 3 # 2 # 0.5 = 3000 liters.
b) Which OXYDATOR should be used?
The OXYDATOR W is the only one advisable for ponds. Duration time is not predictable in a pond, through to different water temperatures, and the very small oxygen bubbles can't be seen. So, time to refill the OXYDATOR is only to recognize if the OXYDATOR floats up to the surface. Only the OXYDATOR W will float.
c) Which OXYDATOR-solution is appropriate?
A lot of ponds have 1.000 liters or more, in these cases only 30% OXYDATOR-solution is applicable. For ponds below 1.000 liters volume 6% OXYDATOR-solution must be used.
d) Could it happen, that one needs some additional catalysts?
Yes, for ponds which were running with 6% OXYDATOR-solution and have more than 250 liters. For example, a pond with 700 liters needs two more catalysts, which were simply put to the other catalyst in the acrilic container. By running 30% OXYDATOR-solution only one catalyst is basically used.
e) At which depth the OXYDATOR should be set in?
Basically it should be set in at the deepest point, because there is the biggest lack of oxygen. On the other hand it is possible, that at the deepest point water temperature is more or less stabil and the OXYDATOR is producing less oxygen than needed at shallower and warmer regions of the pond. A proved method is to put the OXYDATOR at the deepest point in wintertime and between 60 and 80 cm at summertime.
f) When does the OXYDATOR has to be refilled??
When it's empty! The OXYDATOR W will float at the surface when it's empty. The OXYDATORS for aquaria won't float, but you can see oxygen-bubbles coming out, if you can't see bubbles anymore, the OXYDATOR might be empty.
g) Does the OXYDATOR also works against algae?
Yes, but it can't be guaranteed for all ponds and all algae, because there are so many species of algae and the environmental circumstances of all ponds are too complex and different. However, the OXYDATOR is a well-proved system to fight against algae. Some floating algae are very obstinate, but also there the OXYDATOR helps on a longterm effect, when you have enough waterplants in your pond. Waterplants takes nutrition (fishfood, rotten material...) and get supported strongly by the OXYDATOR, so that algae get starved.
h) Is it possible to combine the OXYDATOR and a CO2-diffusor in a fish-tank?
Yes, CO2 or carbon dioxide is the highest oxidation level of carbon, it can't be changed through oxygen and CO2 is much more dissolvable in water than oxygen, so that there is no influence against each other. You have to take no notice, if you using an electronically controlled CO2-diffusor. Using an uncontrolled CO2-diffusor you have to take notice that by oxygen supply with the OXYDATOR: 1. no expelling of CO2 happens, 2. CO2 is produced additionally through oxidation of organic material, like fish excrements, fish food or dead plant material.