Top Protein Skimmer Fixes & Why They Work!

Categories: BRStv Investigates, Protein Skimmers, BRStv Problem Solvers

Last updated: Jan 25, 2022

If you struggle with getting consistent performance out of your protein skimmer or simply want to ensure your taking the best possible approach to skimming your tank, this list of helpful skimmer fixes is sure to help. Not only do we give you the solutions for the most common problems people face with a protein skimmer but you also get a detailed explanation of why it works.

1. Reduce The Air To Stabilize The Foam

This works to help prevent that frustrating skimmer that just won't produce any skimmate even though you're getting frothy foam in the skimmer body. Usually indicated by fast-boiling bubbles that just pop at the surface but don't seem to slowly rise and collect waste. There are a few ways to reduce the air intake depending on the particular skimmer you have.

If your skimmer has a DC controllable pump, simply slow down the pump < most-effective
Raise the skimmer on a skimmer stand
Lower water level around the skimmer
Add an air valve to the airline and slowly dial it back < last resort

Why It Works

By reducing the air, you are effectively tuning the skimmer to meet your tank's particular nutrient level. If a skimmer is pulling too much air and there are not enough nutrients in the water, the bubbles just rise fast and pop without carrying any waste/skimmate up into the cup. By reducing the air into the skimmer, you can slow the bubbles down and create a bit more contact time so they can effectively come together and rise into the cup, carrying waste.

Essentially your skimmer is running too lean, with not enough nutrients (fuel) for the amount of air going into the foam engine (skimmer). Tuning a protein skimmer is all about the nutrient to air ratio where the more nutrients you have, the more air you will need to effectively skim the water. Protein skimmers that are too big/powerful for your tank's particular nutrient level won't work for this exact reason, they pull too much air. Having the ability to fine-tune that air intake can be a big help and using a skimmer with DC controllable pump is the most effective approach.

2. Almost There, Add More Air!

This is essentially the exact opposite of the first problem where you can achieve a thick foam head but it's not climbing into the cup no matter how you adjust the internal foam level. This often results in thick mud gathering on the inside of the skimmer body and neck but not much skimmate in the cup.

If your skimmer has a DC controllable pump, increase the pump speed < most-effective
Raise the water level around the skimmer

Why It Works

In this scenario, there is too much waste in the water and the skimmer is not able to push the skimmate up into the cup because it doesn't have enough air. If raising the internal foam level via the outlet pipe doesn't work, your skimmer is likely just underrated for your particular bioload. Having a skimmer with that DC controllable pump is highly beneficial here because it gives you much more flexibility to adjust that air/nutrient ratio properly. Skimmers with a fixed flow AC pumps just don't have the range of adjustment like you get with a DC skimmer.

3. Set The Foam Level First, Then Tune The Air

When setting up your skimmer, it is best to first set the foam level using the outlet pipe then fine-tune the collection by adjusting the amount of air thereafter. Water level first, air adjustment second.

Set the foam level to match the top of the skimmer body; where the collection cup connects to the skimmer body.
Wait 24 hours and adjust air accordingly. If you want wetter skim, add more air. If you want a drier skim, reduce the air.

Why It Works

When you adjust the foam level inside a skimmer, you are actually changing the rate at which the pump pulls air and water into the skimmer because of the head pressure it creates/reduces. You want to have that foam level set at the correct height before you go fine-tuning the amount of air going into the skimmer which will always result in the best performance. This is especially true with DC skimmers where you have the ability to change both the pump speed and foam level - adjust the foam level first then adjust the pump speed to accommodate your nutrient levels.

4. Tune It Until It Stinks

A skimmer should pull smelly skimmate. If it doesn't smell when you clean it, it's not working right.

Follow the previously outlined approaches to tuning your protein skimmer.

Why It Works

By design, a skimmer removes fish poop and decaying organic matter which always smells. If you're not getting a strong sulfur smell when cleaning the collection cup, the skimmer isn't working properly. Trying to tune the skimmer should be your first step and if you just cannot get it to work correctly, the skimmer may be broken or just over-rated for your particular tank size.

5. If All Else Fails...

If you have tried everything you possibly can to tune the skimmer but it still won't work, it probably means the skimmer is too strong or just over-rated for your particular tank size and bioload.

Pull your felt filter socks and replace them with mesh socks; this allows more waste to stay in the system
Get a new skimmer that is more appropriate for your tank size.

Why It Works

A skimmer must be appropriately sized for your particular bio-load to work properly. If the skimmer cannot seem to be tuned correctly but seems to be operating as it should, it's likely just over-rated for your particular bioload. A skimmer that is oversized will almost never work while a skimmer that is too small will always work, it just may not pull as much as you would like.

When shopping for a skimmer, scaling down is always the best approach. This is yet again another reason why DC controllable skimmers have a big advantage. A DC skimmer gives you a much wider range of control meaning you can more effectively tune the skimmer to meet a wider range of nutrient levels compared to a fixed-flow AC skimmer.