Fluval Sea Evo 13.5 Review

Fluval Sea Evo
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    From one of the most well-known brands in reef tank products comes a brilliant starter tank for anyone wanting to try their hand at a saltwater reef tank. Read our Fluval Sea Evo 13.5 review.

    Fluval Sea Evo 13.5 Design

    One of the key selling points of the Fluval Sea Evo 13.5 is the design itself. All of the equipment is completely hidden behind a black plastic wall. This includes the filtration system and the heater and any other items you don’t want on display. All that’s left on view is what you really only want to see, the sand, rock, corals and fish….and maybe some water too. There is a separate lid for the filtration area which is a nice little feature allowing you access to the surprisingly spacious filtration area. Inside the tank, there is a twin output, which is multi-directional to allow customized water flow.

    Fluval has cleverly added a black honeycomb section surrounding the top area of the glass, this hides the top of the water, and is surprisingly effective as it’s hardly noticeable at all. The lighting is Incorporated into the hood and is well hidden. Next to the edge of the lighting module is a small opening for feeding your tank inhabitants. I have a seen a few complaints that the feeding hole does not have a cover, but I don’t think that is a big deal. The opening is pretty small, so the chances of any fish jumping out are pretty insignificant. Additionally, on the hood there is a partially punched-out area where a skimmer can be fitted.

    fluval sea evo review
    Fluval Sea Evo 13.5 review

    Fluval Sea Evo Lighting

    The in-built lighting system is LED as you would expect and displays a brightness in the daytime setting of 1380 lumens with a color temperature of 14,000K. The lighting for the Fluval Sea Evo 13.5 was specifically designed for coral growth. However, most owners of this tank will confirm that it is not sufficient for growing SPS corals. This tank and its lighting are sufficient for Softies and some easy-to-grow LPS. While the lighting is not sufficient for all corals, for a nano tank it does allow for a reasonable variety of corals, certainly enough to make it look attractive and still wow your friends.

    Fluval Sea Evo Filtration

    To allow the owner to hit the ground running, everything is included in the filtration department. The Fluval Sea Evo 13.5 comes with a 3-stage filtration system with oversized media for good water quality. The central chamber includes a sponge block with cut-outs to add a carbon insert and a BioMax insert, all of which are included. While many reef tank owners will say that the included filtration items are not sufficient, it is enough to get started. You can then upgrade items as-and-when you feel the tank needs it.

    The 3-stage filtration block sits in the middle chamber of three. One one side of that you have the pump which connects to the outlets with a connected tube. On the other side there is an empty chamber where you can place a heater, or even a skimmer if you want to. Above the third chamber there is a little slider that allows you to set the desired water level of the tank.

    Fluval Sea Evo 13.5 Upgrades


    A common upgrade is to switch out the provided sponge block with an InTank media basket in chamber one. This is then fitted with filter floss, Purigen and Chemipure Elite.


    The provided pump gives a basic level of flow. Many reefers would say a more powerful flow is required to be successful in growing corals. Several brands make good quality pumps that will fit in the provided space allowing you to upgrade the pump provided. Alternatively, another option is fit a small powerhead into the tank itself.


    While the included standard lighting is sufficient for “easy” type corals, some who are looking to grow more light-demanding corals may wish to consider upgrading the lighting. A popular choice to is switch to AI Prime, and there are a few ways that this can be achieved on the Fluval Sea Evo 13.5, one of which is to replace the plastic lid with stiff mesh.

    Negative Aspects to Owning this Tank

    While tank is solidly built, well-designed, and includes everything you need to get started in the reef tank hobby(apart from a heater), it’s main downside is it’s size. This is not a design flaw as such, and you get the tank size you pay for right? but the overall tank size is it’s Achilles heel. 13.5 gallons is considered to be very small, nano in fact.

    The biggest issue with this size tank, is that if something goes out of whack within the water parameters it can rapidly adversely affect the tank’s inhabitants. While the same water parameter issues exist in larger tanks, it will tank much longer for the issue to affect the inhabitants, thus giving the owner more time to notice and resolve the issue. As this tank is predominantly aimed at the beginner market, this problem may put off the beginner entirely after going through their reef tank crashing and losing their inhabitants.

    It would be useful to clearly explain on the box what a realistic use of this tank can be. Many people new to the hobby walk into a LFS and see all the corals without knowing what is involved. Buying this tank we believe it should clearly state what it is best suited for and state its limitations, particularly with regards to which types of corals can be successfully grown, especially with the supplied lighting.

    Fluval Sea Evo
    Fluval Sea Evo 13.5


    We hope you found our Fluval Sea Evo 13.5 review contained We believe this tank is a great way for someone new to the world of reef tanks to make a start. Yes, it has it’s limitations, but that’s just mainly due to it’s size. It is a well designed and great looking tank, and provided its owner does a little research, and thinks about it’s limitations, it can turn out to be a very nice looking mini reef in your living room.

    Once a beginner spends some time with this tank, and gains knowledge of maintaining a healthy reef tank, they will no doubt wish to get a larger tank. This is not a negative with regards to the Fluval Sea Evo 13.5, but its really a compliment, as this tank should be considered a stepping stone on the reef tank journey. People who have started their journey with this tank, will look back with fond memories!

    Our Verdict

    Probably the best starter tank around for someone looking to make a start in the reef tank hobby. Highly affordable and includes pretty much everything you need to get started.


    • Brilliantly designed
    • Very affordable
    • Complete kit includes all you need
    • Perfect starter tank


    • Size of tank can be limiting

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