- Joined
- Aug 29, 2011
- Location
- Sarnia, Ontario
whats the differnce between the in sump skimmers .....normal and recirculating ones
skimmers
- Thread starter Petercar (RIP Dec 2017)
- Start date
AdInfinitum
Super Active Member
- Joined
- Jan 12, 2012
- Location
- Thorndale, Ontario
On a regular skimmer the pump pulls water from the sump, mixes it with air, sends it through the reaction chamber and then it exits. So flow through rate is fixed by the flow rate of the pump and contact time is fixed based on the volume of the skimmer body. A big pump that pulls tons of air will also flow a lot of water requiring a larger body to allow good contact time.
A recirc skimmer has a feed pump or a valved gravity feed that controls flow through rate, while the needlewheel/venturi pump draws water from the skimmer body mixes it with air and injects it back in. Since the point of the design is for the feed to run significantly lower volume than the recirc pump, water in the skimmer body will be processed and re-processed before passing through giving longer contact time in a smaller body and you can tune the contact time by changing the flow through rate...in theory.
Much of modern skimmer design is aimed at maximizing air/water contact time without having a six foot long pipe behind your tank like in the old days.
A recirc skimmer has a feed pump or a valved gravity feed that controls flow through rate, while the needlewheel/venturi pump draws water from the skimmer body mixes it with air and injects it back in. Since the point of the design is for the feed to run significantly lower volume than the recirc pump, water in the skimmer body will be processed and re-processed before passing through giving longer contact time in a smaller body and you can tune the contact time by changing the flow through rate...in theory.
Much of modern skimmer design is aimed at maximizing air/water contact time without having a six foot long pipe behind your tank like in the old days.