Seachem Plant Substrates and Additives

Seachem Plant Substrates and Additives can help you achieve a beautiful planted aquarium.

Planted aquariums continue to gain popularity within the aquarium hobby, and Seachem has a variety of products that will make any hobbyist successful with a planted aquarium. In this review, I tested four of Seachem’s substrates that are specifically for planted aquariums. I also tested some of their additives for plants.

 Seachem substrate

The Claims
Seachem’s claims for their substrates and additives are very simple — your plants and planted aquariums will be better with their products.

The Tests
I actually did two separate tests.
1. I tested the four Seachem plant substrates to see if there was any difference between them in growing plants.
2. I used two of Seachem’s substrates and three of their additives in a typical planted aquarium setup.

Four Substrates: The Test
I set up a 29-gallon aquarium with glass siliconed on the bottom to divide the bottom into four sections. I put Onyx Sand, Flourite Black, Flourite Dark and Flourite Sand each into one of the segments. The aquarium had a 4-foot reflector (I didn’t have a 30-inch one, so it hung over one end) with two T-5 lamps, one white and one actinic blue. Twelve zebra danios were the inhabitants, and in each quarter of the bottom I planted the same amount of anachris (Egeria spp.), Rotala indica, narrow-leaf hygro, a crinum and some Cryptocoryne wendtii. The light was on for 10 hours a day, and I ran the test for two months.

Four Substrates: The Results
In all four of Seachem’s substrates for planted aquariums, the plants did very well. The Egeria did the best, requiring trimming twice in the two-month test period. The substrate that grew the best aquatic plants was clearly the Black Sand. When I pulled up the plants to see how their root systems were doing, both the Egeria and Rotala growing in the Black Sand had by far the best roots, and they were actually tough to pull out of the Black Sand. All four Seachem substrates did well.

Planted Aquarium with Additives: The Test
The other test I did (also reporting here at two months) was to set up a standard 50-gallon aquarium for a low-tech (no carbon dioxide injection and low to medium light levels) planted aquarium system. I mixed Flourite Dark and Flourite Black Sand together in equal amounts for the substrate, with 60 watts of LED light on for 10 hours a day. Fish were schools of jumbo neons, diamond tetras and glowlights, with a bunch of otos, Siamese algae-eaters and two skunk botias for snail patrol. Plants were red Ludwigia, red hygro, Rotala indica, Java ferns (both normal and narrow-leaf varieties) and large Amazon sword plants with mottled red leaves (Echinodorus rubin and E. ocelot). I added Seachem Flourish, Flourish Excel and Flourish Iron, according to the directions.

Planted Aquarium with Additives: The Results
Put quite simply, I have never had as gorgeous a planted aquarium as this 50 gallon using Seachem’s products for planted aquariums. The plants all grew vigorously. The stem plants grew up to the surface of the water and spread out nicely. The Amazon sword plants all grew strong leaves. Their root systems were so deep that I gave up on removing one sword plant that had grown very large because the roots were so strong that I would have pulled up half the the aquarium to get it out. The Java fern went completely nuts. What impressed me the most was all of the reds that were brought out in many of the plants. The leaves of the E. rubin were dark ruby red, and the three red stem plants had the best colors I have ever seen in any of my planted aquariums.

Also, of great importance for most hobbyists, there was never any algae in the aquarium from day one. The plants did so well with the Seachem products that algae never had a chance to get going.

The Seachem products for planted aquariums that I tested were all excellent, and their claims proved to be completely true. I recommend that any hobbyists wanting lovely planted aquariums with very little effort take advantage of the research and care that Seachem has put into developing these products.

Plant substrates and additives


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