RSK300 is the worst skimmer I've ever owned.

Reefin' Alaska · May 24, 2022

I have an RSK 300 on a RS 300XL.

In 9 months this thing has never produced decent skimmate. I've tried everything.

Raising it. Lowering it. I removed my C02 scrubber. Removed the neck cleaner. I've cleaned it twice a week. Replaced the air tube thinking maybe it was sucking in water. Nothing. More crap collects in the neck than darker skimmate in the collection cup.

Last straw last night, had good foamy bubbles, but producing no skimmate, made probably 1/16th of a turn to have the bubbles come a bit further up the neck. Look this morning, the bubbles are no longer small and foamy, it's big watery bubbles, producing this watery skimmate and the cup is barely brown and half full. This has been a constant battle with this thing.

92Miata · May 24, 2022

The "Tiny adjustment turns skimmer from too dry to too wet" is kind of the hallmark of a skimmer being too deep in the water.

jlmccrarey · May 24, 2022

Absolutely love mine

SteveMM62Reef · May 24, 2022

Are you using Silicone Lube on any part of the Skimmer or in the System? Silicone Lube will stop a Skimmer from working.

wolfen281 · May 24, 2022

SteveMM62Reef said:
Are you using Silicone Lube on any part of the Skimmer or in the System? Silicone Lube will stop a Skimmer from working.

SPS2020 · May 24, 2022

What is the water level in the sump? There is a red label on the acrylic rod for the water level. That will absolutely make a difference in performance.

I agree, take out that crappy skimmer neck cleaner...total garbage. I used silicone to fill in the holes in the cap and like the performance much better.

helmsreef · May 24, 2022

I run a RSK600 on my big set up and an RSK 300 on my smaller setup and both perform excellent, but they are very sensitive to water height

ReefRondo · May 24, 2022

I run both the 600 and 900 and they are the best skimmers I’ve ever owned. Sounds like you have a depth issue.

ReefRondo · May 25, 2022

SPS2020 said:
What is the water level in the sump? There is a red label on the acrylic rod for the water level. That will absolutely make a difference in performance.

I agree, take out that crappy skimmer neck cleaner...total garbage. I used silicone to fill in the holes in the cap and like the performance much better.

My neck cleaners work really well. What issue do you have with yours?

Reefin' Alaska · May 25, 2022

This is not a water height issue. I've tried raising the water level in the skimmer section above the water line sticker, as well as to the point where it's 1-1.5" below that sticker - this isn't an issue that cropped up a few days ago, this has been going on for months.

SPS2020 · May 25, 2022

ReefRondo said:
My neck cleaners work really well. What issue do you have with yours?

The issue is they hold the skimmate in the skimmer with the possibility of it dropping down into the bubble chamber. I'd much prefer just to remove and clean.

SPS2020 · May 25, 2022

Kurant said:
This is not a water height issue. I've tried raising the water level in the skimmer section above the water line sticker, as well as to the point where it's 1-1.5" below that sticker - this isn't an issue that cropped up a few days ago, this has been going on for months.

I don't have an answer for you, but agree that it is also the worst skimmer I have owned as well. However, it would probably be consistent with a few others on the market now. For me, the issue is there are too many parts. My old school EuroReef CS6 is a dream in comparison. It works wonderfully and consistently. There are no baffles, no neck cleaners, it has a union instead of a slip on collection cup, etc. All this makes it extremely easy to clean all parts. The only reason I chose the RSK was due to the small footprint necessary for the Trigger sump. Hopefully, you will find resolution. Worse case scenario, just sell and try another brand.

Reefin' Alaska · May 25, 2022

SPS2020 said:
I don't have an answer for you, but agree that it is also the worst skimmer I have owned as well. However, it would probably be consistent with a few others on the market now. For me, the issue is there are too many parts. My old school EuroReef CS6 is a dream in comparison. It works wonderfully and consistently. There are no baffles, no neck cleaners, it has a union instead of a slip on collection cup, etc. All this makes it extremely easy to clean all parts. The only reason I chose the RSK was due to the small footprint necessary for the Trigger sump. Hopefully, you will find resolution. Worse case scenario, just sell and try another brand.

I am thinking of going with a Nyos 160 or a Maxspect Jump SK400. Both available to me locally.

The purpose of the RSK300 for me was the same, it fit the 300XL sump nicely.

I just wonder if perhaps my filter roll has made this thing effectively useless, as I don't have that much bioload with only 5 small fish in it. (which will be 2 shortly when I move the anthias over to the CADE.)

Silent · May 25, 2022

Kurant said:
I am thinking of going with a Nyos 160 or a Maxspect Jump SK400. Both available to me locally.

The purpose of the RSK300 for me was the same, it fit the 300XL sump nicely.

I just wonder if perhaps my filter roll has made this thing effectively useless, as I don't have that much bioload with only 5 small fish in it. (which will be 2 shortly when I move the anthias over to the CADE.)

I think you may be right about using the filter roller in conjunction with that skimmer with only 5 small fish. There really couldn't be that much matter for the skimmer to remove right?

blaxsun · May 25, 2022

Silent said:
I think you may be right about using the filter roller in conjunction with that skimmer with only 5 small fish. There really couldn't be that much matter for the skimmer to remove right?

I've read of a few other issues with a particular brand of fleece roll and skimmers, but I don't know if this is something related to the skimmer in question.

Poochaku · May 25, 2022

Kurant said:
I am thinking of going with a Nyos 160 or a Maxspect Jump SK400. Both available to me locally.

The purpose of the RSK300 for me was the same, it fit the 300XL sump nicely.

I just wonder if perhaps my filter roll has made this thing effectively useless, as I don't have that much bioload with only 5 small fish in it. (which will be 2 shortly when I move the anthias over to the CADE.)

It sounds like you don't have enough bioload for the skimmer thus making the sweet spot for getting good skimmate extremely narrow... before switching skimmers, I would see if bypassing the filter roller improves skimmer performance, just as a quick test to see if the skimmer is really the problem.