Microbubbles often go hand-in-hand with protein skimmers when they are first added to saltwater aquariums, especially hang on back style skimmers.
Microbubbles usually stop forming after running a new protein skimmer for 1-3 weeks. This is generally referred to as a protein skimmer’s “break-in” period where organic slime is built up inside the skimmer body. Normally the break-in period is 1-3 weeks, although in some instances it may take 4-8 weeks.
Before installing a new protein skimmer, rinse it thoroughly inside and out with lukewarm water to remove any dust or residue left from manufacturing. If you’re using a hang on or external skimmer, you only need to rinse the parts that will have water in them.
If you’ve had your new protein skimmer running for 1-3 weeks and it is still producing a lot of microbubbles, here are some tips that should help you eliminate them from forming:
- While tee fittings work well for many aquarium hobbyists, others have noted they sometimes increase the amount of bubbles being released into the tank. Tee fittings allow you to fully submerge the return line without worrying about a siphoning effect of the water inside the skimmer. For people with limited space in the back of their tank—like nano cubes with built-in filtration—this comes in quite handy. But if you aren't limited on space and can angle your return line, you might try replacing the tee fitting with an elbow fitting (this was actually the original design, the tee was added later on). For some hobbyists, using an elbow helps reduce microbubbles. A tee fitting will sometimes pull air in with the water exiting the skimmer causing extra bubbles to be mixed in. Try swapping out the tee fitting with an elbow fitting and angle the return so it is not submerged and that may do the trick.
- Some aquarium additives and supplements can create a “soapy” effect that causes protein skimmer bubbles not to pop as quickly as they should. Common two-part calcium/alkalinity supplements rarely have any effect, although other supplements can. If possible, limit dosing specific additives/supplements for a few days to see if that has any effect on the amount of bubbles being released into your aquarium.
Water treatments and conditioners can also create the soapy bubble effect, as well as two-part epoxy, red slime (cyanobacteria) remover and some medication formulas. For best results, always use RO or RO/DI water to mix saltwater and top off your aquarium. If you’ve recently used two-part epoxy to attach coral to rock or treated your tank for red slime, we recommend performing several water changes to reduce the presence of these products in your tank water.
- As a last resort, try placing an air control valve on the air intake to reduce the amount of bubbles being pulled into your protein skimmer. While not an ideal solution, an air control valve will allow you to scale back the amount of bubbles that enter the skimmer. You may find this reduces the number of bubbles that flow back into your aquarium. You can usually find air control valves for sale at your local pet store for only a couple of dollars.