Saltwater reef tank and koi pond gear

Salt mixes, test kits, a reef light and koi food, picked from published ratings. Reef gear is better covered than pond gear so far.

Disclosure: Some links on this page are affiliate links, and we may earn a commission from qualifying purchases. How we pick.

Pets this page covers

Saltwater and reef tanks

Saltwater stocking is tighter than freshwater, and nitrates can build up more. Check salinity along with pH, alkalinity, ammonia, nitrite and nitrate about every 2 weeks.

Koi and pond fish

Ponds need grounded waterproof outlets, plants for oxygen, nutrient uptake and shade, and less feeding in cold weather. We have one koi food pick so far and have not verified pond pump or filter picks yet.

What to look for

Commercial aquarium salt supplies needed minerals and helps stabilize pH. Check the salt maker's directions and your tank type for the right salinity. Source: Merck Veterinary Manual
Stocking is tighter in salt water. A common guideline is about 1 inch of fish per 5 gallons. Source: Merck Veterinary Manual
Cycle the tank first. Natural cycling takes about 4 to 6 weeks, and fish should be added gradually. Nitrates can accumulate more in saltwater tanks. Source: Merck Veterinary Manual
Check specific gravity along with pH, alkalinity, ammonia, nitrite and nitrate about every 2 weeks. Service skimmers and replace carbon every 1 to 3 months. Source: Merck Veterinary Manual
Quarantine new fish for 30 to 60 days. Source: Merck Veterinary Manual
For ponds, use grounded waterproof outlets, use plants for oxygen, nutrient uptake and shade, and cut back feeding in cold weather. Source: Merck Veterinary Manual
Mix salt away from the tank, never in a tank containing animals. This comes from the manufacturer label as relayed by Chewy, not an authority source. Source: Instant Ocean label, via Chewy
Wash hands before and after tank care and wear gloves if you have cuts. Dump tank water in a tub or laundry sink, not the kitchen sink, and keep children under 5 and immunocompromised people away from tank chores. Source: CDC

Research picks

These are research picks drawn from published ratings and expert sources, not our own lab tests. Prices and ratings were seen on 2026-10-23 and can change. Bulk Reef Supply shows ratings as a percent out of 100, not stars.

Salt mix Fish-only marine tanks Research pick

Instant Ocean Sea Salt for Aquariums (160 gal bag)

Fish-only and fish-with-invertebrate marine tanks.

Mix with dechlorinated water to make marine water. The label advises a 20% change every two weeks and never mixing salt in a tank with animals in it.

Skip it if: You keep SPS or LPS coral at reef-level demands. Chewy itself points to Reef Crystals for corals.

Price seen: $59.97 on Chewy (list $73.59) | 4.7 of 5, 459 ratings / 199 reviews, Chewy

See it at Chewy Affiliate link

Reef salt mix Reef tanks Research pick

Instant Ocean Reef Crystals Reef Salt (200 gal)

Reef tanks with corals and inverts.

Added calcium for stony corals and coralline algae, plus trace elements, vitamins and a metal detoxifier.

Skip it if: Your tank is fish-only and you are on a tight budget.

Price seen: $84.77 on Chewy (list $99.69) | 4.6 of 5, 361 ratings / 159 reviews, Chewy

See it at Chewy Affiliate link

Test kit Saltwater fish tanks Research pick Limited reviews

API Saltwater Master Test Kit (550 tests)

Beginners checking pH, ammonia, nitrite and nitrate.

A basic saltwater water-quality kit for new marine tanks.

Skip it if: You keep corals, since it does not test alkalinity, calcium or magnesium.

Price seen: $34.99 on Chewy (list $50.48), $35.98 at Bulk Reef Supply | 4.5 of 5, 38 ratings / 21 reviews, Chewy. Bulk Reef Supply shows 76 of 100 from 5 reviews (percent scale, not stars).

See it at Chewy See it at Bulk Reef Supply Chewy link is an affiliate link

Reef test kit Reef tanks Research pick

Salifert Alkalinity (kH) Test Kit

Reef keepers watching alkalinity.

A liquid alkalinity test for reef tanks, good for 100 to 200 tests.

Skip it if: You want digital readouts or less subjective color reads.

Price seen: $16.99 on World Wide Corals (sale), $18.79 at Bulk Reef Supply | 96 of 100 from 86 reviews at Bulk Reef Supply (percent scale, not stars). No rating shown at World Wide Corals.

See it at World Wide Corals Not an affiliate link

Reef LED fixture Mid-size reef tanks Research pick Limited reviews

AquaIllumination Hydra Edge 44HD LED Reef Light

Mid-size reef tanks. The maker spec on Bulk Reef Supply covers up to about 30 x 30 inches at 9 inches above the water.

An LED reef fixture for mid-size tanks.

Skip it if: You need mounting gear included (it is sold separately) or you have a small nano tank.

Price seen: $399.99 at Bulk Reef Supply | 94 of 100 from 13 reviews at Bulk Reef Supply (percent scale, not stars, low volume)

See it at Bulk Reef Supply Not an affiliate link

Floating koi pellets Koi and pond fish Research pick

Hikari Staple Koi Food

Koi and pond fish fed daily. Floating pellets let you watch intake.

A staple floating pellet. The retailer links a feeding chart by water temperature. Every variant showed sold out on 2026-10-23.

Skip it if: You want a color-enhancing diet, since the page says there are no color-enhancing additives.

Price seen: $35.99 at Champion Nishikigoi (sold out when checked) | 4.8 stars from 200+ verified buyers per the retailer's page (not independently verified)

See it at Champion Nishikigoi Not an affiliate link

Check the current price and availability before you buy. Links go to retailers and brands, and none are affiliate links yet. We have not checked recall databases for every item, so look up recalls before you buy.