Red Sea Reefer Skimmers 1000 – RSK300

Specifications

What Red Sea publish for the REEFER Skimmer RSK-300 (part R50503):

SPS-dominant rating 300 L / 80 gal
Mixed reef rating 600 L / 160 gal
Fish-only rating 900 L / 240 gal
Pump Sicce PSK-600
Air flow 500 lph / 130 gph
Water flow 1,000 lph / 265 gph
Total height 53 cm / 21″
Recommended water height in the skimmer chamber 16–20 cm / 6–8″

About the numbers in the title. Red Sea name these skimmers RSK-300, RSK-600 and RSK-900 after the aquarium volume in litres they suit in an SPS-dominant system. The larger figure carried in this listing’s title is the pump’s water throughput in litres per hour, not a tank rating — size the skimmer off the three ratings above.

Red Sea rate these skimmers to their REEF-SPEC criteria, which cover water throughput, the water-to-air ratio and the contact time needed to strip pollutants efficiently. The air and water flow figures are measured with the Sicce PSK pump actually running on this skimmer, not taken from the pump’s own datasheet.

What Red Sea do not publish for this model:

• A power draw in watts
• A weight
• A footprint or body diameter
• A noise figure

Those rows are simply not on Red Sea’s specification sheet or in the manual, so we have left them blank rather than fill them in. If one of them decides your purchase, ask us before ordering and we will put the question to Red Sea.

What’s in the Box

Red Sea do not print an itemised scope of delivery for this product. The list below is built from the parts and components named in Red Sea’s own manual for it. If something on it is missing from your carton, tell us and we will take it up with the distributor.

• Skimmer body with high-volume reaction chamber
• Base with three-position pump holder, cable restraint and rubber feet
• Sicce PSK-600 skimmer pump with rubber damper pad and rubber connector
• Bubble diffusion chamber — diffuser, venturi and venturi tube
• Collection cup with FoamView window and printed graduations
• Lid with the integrated manual neck cleaner (wiper and blades)
• Air intake silencer with air tube and drainage port plug
• Extra-long drainage tube, 1 m / 39″, with elbow connector and watertight valve
• Screw pack (9) and rubber pack

It arrives part-assembled. Red Sea note that the skimmer body is screwed to the base in a position chosen for transport only — you take it apart and build it properly before it goes in the sump.

Setup & Use

Assemble it first, then wet it. Unscrew the body from the base, reposition the pump holder for the orientation you want, turn the base upside down and press the rubber feet firmly home.

Get to know the pump before it goes in. Red Sea recommend stripping and reassembling the pump once before its first fitting, because you will be doing it monthly for the rest of the skimmer’s life. Check the rubber damper pad is in place before pushing the pump into the holder, run the pump cable around the pump and through the cable channel under the base, and put the cable restraint back. Skipping the restraint can affect how the skimmer regulates.

Venturi. Push and rotate it together through the rubber grommet in the body wall and into the rubber connector on the pump inlet, with the venturi air inlet facing up. Wet the outside of the venturi to make it go — never grease it. Clip the silencer into its holder on the neck and connect the air tube between silencer and venturi air inlet.

Where it stands in the sump. Three orientations of the venturi pump inlet relative to the skim regulator — left, centre or right — so it can be set up for your sump’s layout. You need at least 2.5 cm / 1″ of unobstructed water column in front of the venturi inlet and at least 2.5 cm / 1″ of free space above the collection cup so it can come out for cleaning. The rubber feet hold the skimmer 13 mm / 1/2″ clear of the sump floor, so the power cable can run underneath.

Water height. Keep the skimmer chamber at 16–20 cm / 6–8″ and keep it constant — which in practice means running an automatic top-off. A skimmer sitting in a level that moves through the day cannot hold a foam point.

First switch-on. Rotate the skim regulator fully in the Minus direction before the pump is switched on. Minus opens the water outlet in the base, lowering the foam point for drier foam; Plus raises it for wetter foam. Set the regulator so the water level inside the skimmer body sits roughly at the base of the neck.

Break-in. A new skimmer often needs a few days before it works properly, and over-skimming during that period is normal and harmless — harmless chemical residues are being neutralised. Leave the regulator fully Minus and let it settle. If it is still over-skimming after a week, strip the skimmer down and wash it in a slightly acidic solution, then rinse thoroughly in fresh water. A new tank may also produce almost no skimmate at first, simply because there is little organic matter to remove.

Routine. Use the neck cleaner daily — it takes seconds and lets you go 7 to 10 days between washing the cup and wiper. Left uncleaned, the sludge layer in the neck cuts foam production by 30–40%. Pull the pump for cleaning once a month: open the impeller chamber, remove the impeller and rinse everything under the tap. If you wash the cup with detergent, rinse it very thoroughly before it goes back.

Foods and supplements are surface-active and will upset foam production, sometimes violently. Switch the skimmer off before adding them and leave it off until it can foam normally again.

Warranty & Support

This product is covered by warranty as per the manufacturer policy, against material and manufacturing defects from the date of purchase.

Warranty support is handled by us directly. Message our WhatsApp support with your order number and we will diagnose the fault first. Most cases are solved by replacing a single part, so you rarely need to send the whole unit. If the item does need to come back, it ships to our Delhi or Pune warehouse, whichever one served your order, and courier cost in both directions is borne by the customer. Your GST invoice is valid proof of purchase for the claim.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number, or email us if you would rather, and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 72 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.