Thought I would give a quick review of the IceCap K1 Nano Skimmer. I have an Innovative Marine Nuvo Pro 25 Lagoon that has a pretty small chamber to put a skimmer in. I originally tried IM's little BioSkim DC skimmer. It was less than satisfactory on all levels. I was able to improve the performance of the IM skimmer slightly by designing and 3D printing a better venturi, but it still never produce a decent skimmate.
So, on to the review of the K1.
Construction and Materials: The skimmer seems to be very well made and out of the box I was impressed with the construction and materials. It comes with a nice magnetic mount for systems that need it. For the IM25 Lagoon it is not needed. In other reviews of the skimmer, it was noted, that the first version had a less than effective venturi. The newest version of the venturi actually looks like a venturi should, with the intake being shaped as an inverted vortex for flow and resulting in better air induction. The collection cup actually resembles bigger skimmer cups. The lid has a baffle and the inlet is cone shaped. The internal skimmer level adjustment knob is very nice. The knob has engraved directional indications for higher or lower level. I would recommend highlighting these with a permanent marker to make them easier to see. The silencer is a decent size and I talk about noise later in the review. The pump is a little guy with a needle wheel. The pump attachment will be my only gripe about the construction, the pump outlet is friction fit into the bottom of the skimmer via a drilled hole. When you go to remove the skimmer from the system the pump stays behind and you have to pull it out with the power cord. A nut or something else securing for the pump to the skimmer would be nice. To remove the skimmer and the pump together you have to pull both the skimmer and the pump cord at the same time.
Fit in the IM25 Lagoon: Well, that's an easy one, it fits. The second chamber on the IM25 lagoon is a staggering 2.8”x 4”x 7.9”. The 2.8" x 4" foot print doesn't give you a whole lot of room to cram a skimmer in there. The published foot print of the K1 Nano is 2.7" x 3.2" and with it rotated diagonally in the second chamber it fits nicely. The level adjustment knob sits just above the rim of the tank and the cup sticks up a few more inches. The prescribed water level for the skimmer is 7" - 9" and the IM25L second chamber is ~8", so it works out perfectly.
Break In: To break the skimmer in, I ran it in a gallon pitcher with a cup or two of vinegar and RO/DI up to about 8" on the skimmer body for about 4 hours. After that I rinsed it off in RO/DI and ran it for another hour or so in straight RO/DI. Then I installed in the tank.
Operation: After powering on the skimmer I adjusted the bubbles without the collection sup installed to the rim of the body of the skimmer and installed the cup. There is very little noise from the silencer. As a matter of fact there is no noise from the silencer. All of the noise is from the pump itself. That will be my only other complaint about the skimmer. It did take a few days tinkering with the level adjustment to get the skimmer dialed in. This was also another complaint from the other reviews that I read. But, show me a skimmer that doesn't require adjustment to get it just right for the system that it is installed in. My tank only has two little clown fish and some LPS, so my bio load is very low, yet the skimmer still get a decent amount of skimmate every 4 or 5 days. The cup is easy to clean albeit a bit hard to get on and off the skimmer due to the o-ring.
Overall Impression: I would definitely recommend this skimmer for AIO tanks that do not have a lot room for bigger skimmers. It is 100 x better than the IM BioSkim DC that is for sure.