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Medium Build List

I went back on forth on which tank to recommend because for $1,500 there are several good options!

I ended up with the Red Sea MAX NANO.  This build is 20 gallons, and includes the return pump, black/white stand, and the ReefLED 50 Light.

But with a larger system comes a higher cost, and this is significantly more expensive than either the Budget Build or the Small Build.

Key Stats:

Size: 20 Gallons (75 Liters)

Approx. Price: $1,500

Dimensions: 18″L x 18″W x 18″H (46 x 46 x 46 centimeters) Tank

Style: All-In-One Rectangle

Stand Included? Yes

Sump? No

Low Iron Glass? Yes

The Red Sea MAX NANO is my choice for a small AIO tank.  Coming in at 20 gallons in total water volume, this low-iron glass tank pairs perfectly with the included stand.

The MAX NANO comes with a WiFi LED light that can be programmed from your phone.  The rear filtration area comes with a filter sock, plastic bio balls, protein skimmer, ATO reservoir, and a return pump.

While this build does come with a higher price tag than either the Budget Build or the Small Build, It is up to triple in size but still the AIO style which is simple for a beginner.

If you are craving a sump, check out some of the other builds!  But be prepared for a slightly steeper learning curve and a harder hit to your pocketbook!

This build comes with the Red Sea ReefLED 50 light and mounting arm.

Here’s the thing about heaters: they all fail eventually, so keep that in mind.  There are several different types of heaters, primarily glass, ceramic, and titanium.  I’ve always used glass as they are inexpensive and heat the water quickly, but they are also easy to break (I’ve shattered at least two, maybe three!) 

These Eheim Jager heaters have been my go-to since the beginning.  I’ve never had one fail on me in over five years (with proper maintenance of course).  This heater does need to be calibrated, so be sure to pair it with a digital thermometer to narrow in on the temperature.

By the way, this 30-gallon tank requires the 100 Watt Jager!

CaribSea’s Life Rock Shapes come in unique shapes, are sustainably made (not pulled from real reefs), and have a coralline algae colored surface which gives them that living reef look on day one.

Live Rock is important for a few reasons:  it provides a place for beneficial bacteria to colonize; it provides hiding places for your livestock; it gives you places to mount coral; and it is better than looking at an empty tank!

With  the size of this build, you may be able to get away with just the 20 lb box, but you may end up purchasing 20 more pounds!

I own a couple different types of scrapers, but this Pro-Scraper II is my go to hand-held algae scraper (did I just use the word “scraper” four times in that sentence?).  You may have peeked to the next item and asked yourself, “why is My First Fish Tank recommending two algae scrapers?”  A valid question, and the answer is “convenience.”

If you just want one scraper, purchase this one, but rest assured that at some point in the near future you will long for the ease and simplicity of a magnetic scraper!

For this size tank, I think the 12″ would work, but you might want to go with the 16″-24″ adjustable so you don’t have to get your hands wet!

I’ve owned this Flipper for several years, and the fact that you can switch between the stainless steel blade and the soft felt side without getting your hands wet is just too convenient to pass up! I’m pretty sure you want the regular size flipper, and not the nano!

For this build, I would probably go with the 9″ medium size.  If you get the mini it will suck up sand way to easily, and if you go with the large, it will drain the tank too quickly!

A gravel vacuum is a must in this hobby for water changes.  It is the easiest way to start a siphon and drain your water, while at the same time vacuuming your sand bed free of detritus.

I probably have owned about 10 of these in the past several years, and they work well for how inexpensive they are.  I’ve tested three of these at a time in the same tank, and they were off by no more than 1.5 degrees F.  Not too bad considering!

two small waterproof digital aquarium thermometers on white background

A basic test kit is a must.  It is most important when you are starting your tank so you can test for when the nitrogen cycle is completed.  While not always the easiest to read, this test kit is affordable and will give a ballpark which will be good enough.  

front view of api saltwater test kit in original packaging

Another nice thing about this build, is that it comes with a return pump!  If it doesn’t give you as much flow as you want, you can always upgrade it down the line to something with a higher flow rate.

Extremely inexpensive, every aquarium hobbyist needs a net!  Not only is it good for catching and transferring fish, you can also use it when thawing frozen food to help get rid of any fillers or phosphates!

It does need to be calibrated, but rather than buy an entire bottle of calibration fluid, just go to your LFS (Local Fish Store) and ask to use a few drops of theirs!

Buying an auto top off unit is not an absolute must for this build, but if you don’t, you will likely need to add 1/2 gallon of RO/DI water everyday by hand.  That gets to be a pain in the butt real quick, trust me on this!

This ATO unit from Reef Breeders comes with everything you need including the pump and silicone tubing.  Just put it on the rear of your tank, attach it to a 5-gallon bucket of RO/DI or distilled water, and you can forget about all the evaporation for a week!

I own two of these, and they work great for the price.

close up view of auto top off unit on white background

For around $35 you can control your tanks temperature to within 0.1° F.  I live in the desert, so in the summer I run a fan to keep my aquarium cool.  I plug my fan into the “cooling” outlet and my heater into the, you guessed it, “heating” outlet, and my tank stays a constant 78° F all year round.  Plus, this controller has a built in alarm which alerts me if my heater or fan ever fail.  Not bad for under $35!

black and grey temperature controller with probe sitting on white surface

Sand is not essential by any means, and there is a trend in the hobby toward a bare bottom tank.  That being said, sand does lend not only a nice aesthetic, but it aids in biological filtration, and provides a refuge and food source for certain creatures.

There are many types to choose from, but I would go with 20 lbs for this build.  My favorites are the Arag-Alive Special Grade, Arag-Alive Fiji Pink, and the Arag-Alive Hawaiian Black.

wet live sand for saltwater aquariums
Fiji pink sand in 20 lb bag with close up of grain size
hawaiian black sand in 20 lb bag with close up of grain size

I currently own four or five of these!  They are my inexpensive answer to an expensive controller.  I mount these either under my stand, or somewhere out of the way and then label each cord.  That way, whenever I need to do maintenance, I can just flip the individual switch to turn off the appropriate piece of gear.  I love these things and will keep recommending them well into the future!

Tripp Lite 7 Outlet Surge Protector Power Strip

While this is technically optional, if you plan on having fish (which I’m assuming you are), then this is a virtual necessity.

Fish jump!  Maybe they are spooked, maybe they are just playing around but regardless we don’t want them to jump out of their tank!

Little known fact about fish…they need water to breath!  Okay, you get the point.  

This kit comes with everything you need, including a clear mesh screen which is great because it let’s way more light though then your typical window screen.

Optional Items

There are so many different types of salt mix on the market, and I’ve tried a ton of them!  They all work fine, but they vary depending on your livestock plan.  

Most of us start out by buying saltwater at our LFS (local fish store), because purchasing distilled water from the grocery store is expensive, or buying the necessary RO/DI filter costs even more.

But you can save a bit of money and hassle in the long run by mixing your saltwater at home.

For this medium build I recommend this salt, as it is good for FOWLR (Fish Only With Live Rock) systems, or tanks with a light stocking of corals.

If you are only planning on keeping fish in your saltwater aquarium, then you don’t need to worry about calcium and alkalinity.  But SPS (small polyp stony) and LPS (large polyp stony) corals, as well as invertebrates such as snails and crabs, need calcium and alkalinity to build their skeletons. 

Of course you don’t need to make your own RO/DI water.  You can either use distilled water (expensive), buy pre-made saltwater from your LFS (local fish store), or buy RO/DI water from your lfs.  But for under $200, you could skip all that and make your own water at home.  

An RO/DI filter was one of my first purchases because I refused to lug 5-gallon jugs back and forth from my LFS, and I didn’t want to buy gallon after gallon of distilled water.

I’ve owned my RO/DI filter for well over five years, and it is one of the best investments I’ve ever made.

A super quick note… don’t drink RO/DI water.  RO water is safe to drink, but RO/DI water is so pure that it may actually dehydrate you and suck nutrients from your body!  Just an FYI!

This may seem like a silly thing to add to a build list, but I have found that these two brushes do the brunt work of my cleaning.  They have a stiff bristle and have held up for me for many years now. They work much, much, much better than a toothbrush!

If you bought the RO/DI filter that I recommended in this build, you don’t need a TDS meter.  That’s because the RO/DI filter comes with an inline TDS meter already!

You could still get one because it’s kind of fun to test the TDS of different things!

Your goal when making saltwater is to have 0 TDS in the RO/DI water before adding salt. 

Just for reference, when I lived in Seattle the tap water had around 40 ppm TDS. I now live in Southern California and my TDS is 140 ppm.

TDS Meter Water Quality Tester

My favorite utility pump is the Cobalt MJ1200, but for some reason (at the time of writing this), they are out of stock everywhere!  I’m thinking they had a production issue and are trying to catch back up with demand?

I’ve never actually owned this utility pump, but it’s made by the Italian company Sicce and I love their pumps!

I use my utility pumps to mix saltwater, pump RO/DI water into the reservoir, provide flow in my quarantine tank, and to clean my sump.  They are just so handy to have around that I own several and use them weekly.