I have heard this before in regards to this Skimmer as you need to "fine-tune" it. This is one of those skimmers that you have to continually adjust which will cause varying results.
What size tank do you have and which model of this skimmer?
I am selling a used 125 gallon Oak aquarium and matching stand (3 years old almost). The first reasonable offer takes it but needs to pick it up. I am located in Hoboken, NJ (zip code 07030)
The tank is not drilled and does not have built in overflows. No cracks, leaks or anything like that.
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