Let’s see how to set the skimmer. 
L’articolo in italiano su come regolare lo schiumatoio lo trovate cliccando qui.
We began last week the topic of the maintenance of the skimmer (article). We’ll now focus on mono pump skimmers but the suggestions are absolutely general.
The first thing you have to know it’s that the skimmer is deeply influenced by the salinity of the water. More the water is salty, more will be the foam. Many times there’s not this attention, but it’s an essential passage (in fact the skimming theory doesn’t work for freshwater). If you don’t want to make mistakes, we suggest you to keep the salinity valour to 35 for thousand, or 1023,3 g/dm3 with 25°C of density. You can read this article to deepen this topic.
Preliminary operations
Once set the right level of salinity it’s important to read the producer’s specifics and where is recommended the height of the water in sump where the skimmer will work better.
Usually if you have not any other indications, a value about 21 cm is a good start. In my new sump, that you can see here above, I chose to keep 20 cm so the skimmer will work in a fixed level of 21 cm.
A fixed height in sump allows to obtain a perfect regulation of your own skimmer. Usually a double pump skimmers (with an input pump) suffer less the variation of the level in sump.
Even an oscillation of 1 cm can make the skimmer over foam or under foam, depending on the level of the variation.
In order to avoid considerable oscillations it’s necessary to use an automatic top up system. If shouldn’t be possible to avoid the oscillations it’ll be better setting up the skimmer on the higher level.
How to regulate a mono pump skimmer (and the others)
Usually the skimmer is regulated by a couple of parameters: water and air inlet. Each producer has a different idea of what their proper relationship is. Let’s see anyway how to obtain the best from our skimmer.
Except for skimmers with unconventional shapes (like the Tunze 9415 in the previous picture) and so one, the purpose is to reach a water level just under the neck of the glass. Normally I prefer to keep the air all open and concentrate on the drain level.
- Open the air totally. Sometimes there’s a little tap, other times a gate valve, or it’s possible to rotate the entrance of the pump (like in Vertex’s).
- Regulate the water to make its level grow till a little over the base of the glass (with the bubbles rising for a few centimeters).
We’re finishing. Sometimes in fact even if you’ve followed these two points may happen that the glass gets full too quickly because the level is too high. In this case you have to change the entrance air, decreasing its percentage.
Now the skimmer is completely regulated.
Continues and ends on page two
