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$340 Budget Aquarium Build

Updated 2024

Welcome to our $340 Saltwater Aquarium Budget Build guide! Our aim is to help you create a stunning saltwater aquarium without breaking the bank. This comprehensive guide focuses on both aesthetics and the quality of equipment, ensuring you get the best value for your money. We’ve designed this budget build to be as close to plug-and-play as possible, making it incredibly easy for you to set up and maintain your affordable saltwater aquarium. Let’s dive in and create a beautiful and budget-friendly underwater world!

While this Red Sea tank is not a budget option, it give you a good idea of what you can build in a small space.

Size: 15 Gallon (57 Liters)

Dimensions: 15″ L x 15″ W x 15″ H inches


The most important and defining gear for your saltwater aquarium build is, without a doubt, the aquarium itself. It sets the foundation for what you can keep inside and dictates the other equipment you’ll need.

In this budget-friendly saltwater aquarium build, we’ve chosen the all-in-one 15 gallon cube from Innovative Marine. This size is perfect for accommodating a variety of corals, fish, and invertebrates without the need for excessive gear or maintenance. It’s versatile enough to fit on a sturdy desk, table, or even your kitchen counter, and you won’t require a dedicated stand.

The cube design of the aquarium allows for an impressive aquascape (rock structure) with depth, creating the illusion of a larger tank. 

This setup is also great because it comes with a ton of stuff:

  • rear filtration chamber
  • adjustable 130 gph dc return pump
  • filter sock
  • self-leveling foam mat

Plus, Innovative Marine has a ton of other gear you can purchase to upgrade your tank, like a pre-made mesh screen, UV Sterilizer, and a custom acrylic caddy.

Plus, Innovative Marine has a ton of other gear you can purchase to upgrade your tank, like a pre-made mesh screen, UV Sterilizer, and a custom acrylic caddy.

close up of a corner of a clear mesh screen with black plastic rim sitting on top of a tank filled with water
IM Mesh Screen


New lights for 2023, the AquaIllumination Blades have taken off.  They come in a lot of different sizes and in four color configurations.  The best general all around is the Blade Grow.  A mix of blues and whites, specifically designed for coral growth

What’s really handy about the Blade light, is it doesn’t need a mount because it comes with detachable feet that it directly on the rim of your tank.

For this IM 15 gallon cube, the 12″ Blade is the right size, and one will work just fine.  I’ve been using one on my 15 gallon HelloReef tank and it has been so good for my anemones!

closeup product shot of a 12" strip style led light with several blue diodes
AI Blade Grow Light

Filtration and Filter Media

Filtering a saltwater aquarium can indeed be a complex and perplexing aspect of the hobby, often leaving us unsure of how to proceed. However, experienced hobbyists will assure you that filtration can be simplified and made easy.

In basic terms, there are three types of filtration that work together to ensure the overall health of your saltwater aquarium:

1. Mechanical filtration
2. Biological filtration
3. Chemical filtration

The good news is that this saltwater aquarium comes a filter sock which is the most basic form of mechanical filtration.

Yes, there are more complicated forms of filtration, but if you change out your filter sock every 3-4 days and perform a weekly 15%-20% water change, it will likely be all you need!

You will want to pick up at least three more filter socks so you don’t have to clean it every three days!

Gravel Vacuum / Siphon

Apart from using filters and filtration media, another essential part of aquarium maintenance is water changes. It’s a straightforward process of removing some saltwater from your tank and replacing it with fresh saltwater. During this procedure, you can also use a siphon to “vacuum” and remove any detritus, such as fish waste and leftover food, from the tank.

For this specific aquarium, I’d recommend the 2″ Medium size.  The 1″ clogs too quickly for my liking.  

Python 2" Gravel Vacuum on a white background
2" Medium Python


An essential piece of equipment for your saltwater aquarium is the heater. As mentioned earlier, stability is key to keeping your aquarium inhabitants happy, so a reliable heater is crucial.

Most saltwater aquariums house tropical organisms that thrive in a stable temperature range between 77-78 degrees Fahrenheit. Unless your house maintains that temperature consistently, you’ll need a heater to ensure the well-being of your aquatic friends. On the other hand, if you live in a very hot climate, you might require a fan to cool your aquarium instead.

Based on personal experience, reputation, and cost, we highly recommend the Eheim Jager TruTemp 50 Watt aquarium heater. It’s a favorite among many saltwater aquarium hobbyists and remains budget-friendly.

Keep in mind that all aquarium heaters will eventually fail, so it’s wise to have a backup plan. Consider getting a second heater as a spare for emergencies. One thing experienced saltwater aquarium hobbyists know is the value of having backup gear!

Aquarium Heater Eheim Jager attached to suction cup base on a white background
50 Watt Heater


We don’t need anything fancy here, just something that is easy to look at everyday and that keeps an accurate temperature.  The BRS Stick-On Thermometer just does that, and is about as inexpensive as they come.  I like to place my stick on thermometers near the rear side of the tank so I can easily check it everyday, but don’t have to stare at it!

A small stick on aquarium heater in cardboard packaging.
BRS Stick On Thermometer


A refractometer is a handy tool used by saltwater aquarium hobbyists to gauge the salinity of their aquarium water. They are highly accurate as long as you let the water warm up to room temperature before taking a reading!  You can also pick up a bottle of calibration fluid as well… that way you will know it’s reading correctly!

Or just pick up this BRS refractometer below and it comes with Refracto Juice… Just salt water pre-mixed to 1.026 salinity.

The exterior grey plastic case for a saltwater aquarium refractometer and a small bottle of calibration fluid sitting next to it.

Water Test Kit

Having a basic test kit is essential for any saltwater aquarium hobbyist. It proves most useful at the beginning of your aquarium journey, allowing you to test for the completion of the nitrogen cycle.

While this test kit may not be the absolute best on the market, it remains affordable and provides a ballpark reading that is suitable for most hobbyists. It serves as a valuable tool for monitoring your aquarium’s health and identifying any potential issues before they manifest as algae or bacteria blooms within the aquarium. Being proactive with testing can help you maintain a healthy and thriving saltwater aquarium.

front view of api saltwater test kit in original packaging. it's a semi-clear plastic box with a blue plastic lid. A label sticker covers the front, it's blue and yellow, and says API Saltwater Master Test Kit on it
API Saltwater Master Test Kit


Rock plays a crucial role in every saltwater aquarium as it serves multiple purposes:

1. It provides a habitat for beneficial bacteria to thrive, aiding in the aquarium’s overall health.
2. The rock creates hiding spots for the aquarium inhabitants, giving them a sense of security.
3. It also acts as a surface for attaching coral, enhancing the beauty and diversity of your tank.

I really like this CaribSea Life Rock.  It’s human made and comes with spored bacteria to help cycle your tank.  This is also their Nano Reef Kit, which is 10lbs of rock with various shapes perfect for this 15 gallon system.

Three pieces of human made coralline colored rock against a white background

Algae Scraper

An algae scraper is a straightforward and practical piece of equipment. Despite maintaining your saltwater aquarium diligently, algae will inevitably grow on the glass. Using a cheap scraper is the simplest way to remove the algae without getting your hands wet and messy. Moreover, when you siphon out the scraped-off algae, you’re contributing to the filtration process in your saltwater aquarium.

Just be sure to get the scraper for glass tanks, not acrylic tanks.

For this budget-friendly saltwater build, we’ve opted for the common hand-held option, which gets the job done effectively. However, if you prefer added convenience, you might consider upgrading to the Flipper magnetic algae scraper, making your aquarium maintenance even easier. Whichever tool you choose, keeping your tank free of algae is essential for a clean and healthy aquatic environment.

Continuum Aquatics Stainless Steel Blade

Fish Net

Having a net is a must for every saltwater aquarium hobbyist, and the best part is that they are incredibly affordable! It’s one of those tools that you’ll find indispensable.

Not only is it handy for catching and transferring fish, but you can also use it while thawing frozen food to remove any fillers or phosphates. The net’s versatility makes it a valuable and practical tool to have on hand for various tasks in your aquarium.

three different sized aquarium fish nets next to each other on a white background
Fish Net

Optional Items

Temperature Controller

Maintaining a stable temperature in your saltwater aquarium is crucial, as we previously discussed. Even the most reliable heating equipment can fail, leading to a complete aquarium crash. However, you can avoid such disasters with a simple and affordable solution priced at just $36. This device monitors your aquarium temperature, ensuring it stays within a precise 0.1° F range and prevents your heater from getting stuck in the “on” position, which could boil your saltwater.

The best part is that this controller can also handle cooling tasks! In my case, living in the desert, I use a fan during summers to keep my aquarium cool. I plug the fan into the “cooling” outlet and the heater into the “heating” outlet, maintaining a constant 78° F throughout the year. This impressive device also includes a built-in alarm, alerting me promptly if there’s a failure in the heater or fan. Remarkably, all these features come at an affordable price, making it an ideal addition to your budget-friendly aquarium build. With this controller, you can rest assured that your aquarium’s temperature remains stable, providing a safe and comfortable environment for your aquatic companions.

Inkbird Temperature Controller


While sand is not a mandatory component, there is a current trend in the saltwater aquarium hobby of having bare bottom tanks. However, adding sand truly completes the genuine aesthetic, making your aquarium feel like a slice of the ocean. Moreover, sand plays a crucial role in biological filtration, providing a refuge and food source for certain creatures in your tank.

If you decide to incorporate sand into your aquarium, a 10 lb bag will suffice. While there are numerous types of sand available, we recommend sticking with the CaribSea brand for its reliability and suitability for your setup. Embracing sand in your saltwater aquarium will contribute to a more natural and vibrant underwater world.

wet live sand for saltwater aquariums close up shot of 10 pound bag
Fiji pink sand in 20 lb bag with close up of grain size
clear bag of aquarium sand with CaribSea label and close up of grain size.
CaribSea Original Grade Ocean Direct

RO/DI Water Filter

The RO/DI filter is a water filtration unit that transforms tap water into nearly pure water through the process of Reverse Osmosis Deionization. To understand its workings in detail, you can read this article.

While some online hobbyists might emphasize the necessity of an RO/DI filter for any saltwater aquarium, this claim isn’t entirely accurate. Although it offers long-term cost benefits and advantages, there are other simpler options for small and beginner saltwater aquariums.

One option is purchasing pre-made saltwater and purified water from your local fish store. Alternatively, you can use filtered water from a grocery store.

Over the course of a year, a $200 RODI filter will save you hundreds of dollars, so while it may seem a bit steep of a price to pay up front, it pays for itself rather quickly.

BRS 4 Stage Value 75GPD RO/DI Filter System

Salt Mix

Many saltwater aquarium hobbyists initially opt to purchase ready-made saltwater from their Local Fish Store (LFS) due to the expense of buying distilled water from the grocery store and the complexities of setting up an RO/DI filter.

However, if you’re looking to save money and simplify your setup in the long run, mixing your saltwater at home is a viable option. With numerous salt mix varieties available on the market, I’ve personally tried many of them. While they all work well, their suitability depends on the specific inhabitants of your saltwater aquarium.

For this budget-friendly aquarium build, I recommend using this particular salt mix. It is ideal for Fish Only With Live Rock (FOWLR) systems or aquariums housing low-demanding corals. Embracing this salt mix will help you achieve a balanced and cost-effective saltwater solution for your aquarium needs.

This Tropic Marin Salt is actually the one I use in all of my tanks.

product close up of white box of seawater mix from Tropic marin with an hand drawn image of a green coral with purple tips
Tropic Marin Pro Reef Salt

Calcium / Alkalinity Test Kit

If your saltwater aquarium is primarily intended for fish or soft corals, you can relax about monitoring calcium and alkalinity levels. In such cases, regular water changes should provide the necessary nutrients and parameters these corals require.

However, if you plan to keep SPS (small polyp stony) and LPS (large polyp stony) corals, it’s crucial to maintain sufficient calcium and alkalinity levels to support their skeletal growth. This kit allows you to determine the ballpark values of these parameters in your saltwater, enabling you to gauge when additional dosing is required or if you may have been overdosing.

Maintaining proper parameters is essential for the health of your aquarium, even if you are diligently managing other aspects. By ensuring the right calcium and alkalinity levels for SPS and LPS corals, you create a thriving and balanced environment for these sensitive organisms to flourish.

I’m going to be honest, this API Reef Master Test Kit is not my favorite.  I much prefer using Hanna Checkers for testing my alkalinity, phosphate, and nitrate.  But, this one is more affordable and works just fine.

Reef Tank test kit new in packaging on white background

Power Strips

One crucial piece of gear you might already have, or need to consider getting, is a power strip to accommodate all the equipment in your saltwater aquarium. While it may be tempting to cut corners here, it’s essential not to skimp on safety. Electrical accidents or fires are serious risks that should not be taken lightly.

Investing in a reliable surge protector/power strip is highly recommended. This particular option not only provides protection but also offers the convenience of turning off individual pieces of gear without having to unplug them. This feature is especially useful during saltwater changes, where it’s advisable to turn off the heater to prevent damage caused by exposure to air while still powered on. By choosing a quality power strip, you can safeguard your equipment, ensure the well-being of your aquatic animals, and create a secure and efficient setup for your saltwater aquarium.

7 outlet controllable surge protector and power strip
Tripp Lite 7 Outlet (controllable) surgeprotector powerstrip

Magnetic Algae Scraper

Among the items in this affordable budget build, the Flipper magnetic algae scraper stands out as an exception. While there are cheaper alternatives available, none can match the performance and durability that the Flipper offers. Personally, I have been using the same Flipper for several years, and it continues to work flawlessly.

One significant advantage of the Flipper is its versatility. It allows you to switch between the stainless steel blade and the soft felt side without getting your hands wet, a feature that any saltwater aquarium hobbyist will appreciate. This magnetic algae scraper not only ensures efficient cleaning but also provides convenience and ease of use, making it a valuable addition to your aquarium maintenance toolkit.

Be sure to get the nano version as it is the correctly magnet strength for the IM 15 gallon tank in this build.

Flipper Nano Float Magnetic Algae Scrper

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