I’m sure this has been debated before but let’s hear it.
This conversation has gotten a lot more complicated over the last five years. When the difference was a $60 bucket of Instant Ocean versus a premium salt around $90, it might have been a $10/month decision. One salt didn’t have to be dramatically better to justify that.
Today, some premium salts are pushing $139 a bucket. At that point, they start to feel more like a luxury product that requires more consideration or justification.
I suggest forgetting what’s popular or what everyone else uses and ask what you actually want from your salt.
- Cheapest option that works: Instant Ocean is an easy pick.
- Stores well: This has become my #1 priority. I want to mix salt once a month at most, preferably every other month. That means avoiding salts with organics, aminos, bacteria, or highly elevated calcium/alkalinity.
- Mixes fast: My #2 priority. I often need saltwater ready within 30 minutes for maintenance or an emergency. ESV’s approach of adding components in sequence dissolves incredibly fast. Nyos mills its salt almost into a powder and is right behind it. Both can be ready in minutes. Many others take hours or even a full day to become truly clear. By “clear,” I mean you can read the lettering on a heater at the bottom of a 55-gallon Brute.
- Stays clean: My #3 priority. I don’t want to constantly scrub brown crud out of the mixing bin. Cleaner raw materials cost more, and elevated calcium/alkalinity salts are also more prone to precipitation.
- Matches my tank: Water changes should improve chemistry, not create another problem to correct. I avoid salts that are substantially different from my target levels. Cheaper salts often run lower in magnesium because magnesium is one of the more expensive components.
- Elemental consistency: I want consistency from the top of the bucket to the bottom and from batch to batch. Grain size, quality of machines used, and mixing time all matter and contribute to cost. In my experience, IO has been the least consistent, while Tropic Marin and Nyos have been among the best. ESV is a standout because many components are already dissolved in liquid, making a homogeneous mix easier to produce. The tradeoff with ESV is that consistency then depends more on the reefer following the mixing procedure correctly.
- Packaging: Packets, boxes, or buckets. I’m a bucket guy, but this is a low-priority consideration.
- Where it’s made: With imported salts, remember that a meaningful part of the price can be freight, tariffs, and another layer of distribution. Not necessary quality. It has been my experience that the Germans target quality as the primary goal and the American companies target Lowest price point.
- Trust: Do I trust the company to make a consistent product, and do knowledgeable people I trust use it?
Summery of various salts Ive explored and if I would use or recommend them.
Instant Ocean — ~$59/160 gal; Reef Crystals ~$67
I used IO for roughly my first five years. If "monthly" salt cost were a meaningful part of the aquarium budget, I’d use it again. For me, though, it often takes a day to become truly clear, dirties the mixing bin faster than most, and has been the least consistent. I would always test it before use. Reef Crystals is the version I’ve personally had the most problems with.
Red Sea — ~$99/175 or 160 gal
I used it for years and produced great tanks with it. The elevated-level Black Bucket gets more attention, but I think the normal-level Blue Bucket makes more sense for most reefers. I no longer use it because it dirties my mixing bins quickly, doesn’t store as well as some alternatives, and the price advantage has largely disappeared. At this point, I’d rather use IO.
Fritz — ~$85/205 gal at 30 ppt
I haven’t used the salt. I’ve tested some of their other products, and based on those experiences it simply hasn’t made my list.
Tropic Marin Pro — ~$139/200 gal
Clean and consistent. I’d comfortably recommend it to someone for whom price isn’t the primary consideration.
Nyos — ~$100/130 gal
This is what I use now. It is
remarkably similar to Tropic Marin Pro but has the levels I prefer and appears to be milled finer, so it dissolves faster. Keep in mind the price is for only 130 gallons, so it isn’t inexpensive. It’s also chronically out of stock, so I tend to buy 6–12 months at a time, preferably on sale.
ESV — ~$107/200 gal
Several people I trust use it, and I really like the approach. I’m simply not willing to do the additional mixing steps. Those steps also get more complicated if you don’t hit the salinity/volume correctly the first time.
Brightwell — ~$111/150 gal
In the testing I’ve done or seen, the levels have generally been much lower than I want. It isn’t really on my list anymore. I’d rather use IO at roughly half the cost.
Aquaforest — ~$76/200 gal
I like their team and the pricing is attractive. I just don’t have enough personal experience with the salt to offer much more than that.
Two Little Fishies — ~$149/200 gal
We all trust and admire Julian, but I’ve had limited experience with the salt itself. For people doing small water changes, the single-use 5-gallon packets are especially attractive.
HW Marine — ~$85/160 gal
My corals reacted very well to it, possibly because of the aminos. The downside is that those organics make it less attractive for someone like me who wants to store mixed saltwater for weeks or months like I do.
One final warning:
the advertised cost per gallon can be very misleading. Some brands quote a legitimate volume at normal reef salinity. Others advertise their gallon count at a much lower salinity than almost anyone would actually use.
Personally, I tend to avoid brands that play that game. If you’re willing to mislead me on something as simple as how many gallons the bucket makes, it makes me question everything else.