Aquarium Guide




Introduction: Aquarium Guide

About: I control electrons to do my evil bidding.

Hello, and welcome to my instructable. In this brief but very informative guide you will hopefully have a clear understanding of how to start and maintain an aquarium. If you want to create a beautiful aquarium like the ones in the pictures above (or not) please read on.

Before we start I recommend finding a good fish store that is not part of a chain. Nothing against the chains, but you'll probably gain more knowledge and help through a locally owned shop. The quality of fish is usually better at a locally owned fish store. If all else fails you can always order fish online. Research the website before making a purchase.


I don't take responsibility or liability for any injury to your fish, aquarium, or yourself. In no way is this instructable the only way to setup and maintain an aquarium. This is not an all inclusive guide and I recommend you read online forums and websites for a complete understanding. The information in this instructable is everything I know first hand or through experience. Results may very and are not guaranteed to come out the same way mine did.

Step 1: Where to Start...

I know what you're asking, where do I begin? What's the very first step to this whole process? Well, it shouldn't be a surprise that you should start with choosing a tank. The best advice I can offer, and others will agree, is to purchase the biggest tank you can afford and properly accommodate in your house. I say this because smaller aquariums actually require more maintenance and are very unstable. It's harder to keep all the parameters in check in such a small tank. If something goes wrong you'll have to fix it immediately. I know this may seem backwards, but it will make sense later when we go over the nitrogen cycle.

Have a clear idea of where you would like to put the aquarium before you head out to the store. Stay away from windows and a/c vents. Placing your aquarium near a window will cause algae. Putting where a/c is blowing on it will make it harder for your aquarium to maintain the proper temperature. Some fish are sensitive to constant temperature changes and can ultimately kill them. Knowing where you want to place your aquarium will give you an idea of what kind of aquarium you are looking for. Most fish stores offer a package deal with everything included. If what you want is in the package, then I say go for it. If you want special equipment not included in the package, then it's probably cheaper just buying it yourself. Then again, you can always sell what you don't need. The decision is up to you. You can also purchase second hand aquariums, this is not a bad idea. You just might have to put some elbow grease into cleaning it.

The size of your tank determines how many fish you can safely keep. You can go by the old inch per gallon rule for stocking. This rule is exactly what it sounds like, an inch of fish per gallon of water. It works but for better accuracy the surface area around the top rim of the aquarium should be calculated and used for stocking purposes. This is recommended because the amount of fish the aquarium is able to accommodate is determined by how much oxygen can be exchanged at the water's surface. Basically, the more surface area exposed to the open air the more fish you can keep. Another thing to consider is the size of your aquarium affects how much your aquarium will weigh. Make sure your floor can support it before you make your decision. Last thing you want is your fish tank crashing through the floor, yikes!

Some handy calculators to help you out:

Aquarium weight calc

Fish stocking calc

Less detailed fish stocking calc

Step 2: So Many Choices...

There are many types of fish to choose from. With that said, it can be overwhelming at first to figure out what to start with. First and foremost ask yourself do you want to start with freshwater or saltwater? If you choose freshwater, great I am one step closer to helping you. However, if you want to go with saltwater I can't help you any further on your journey. Don't let that scare you. Please feel free to find other well written instructables to help you on your way with starting a saltwater aquarium. Ok where were we, ah yes, so there are tons of different freshwater fish to choose from. Depending on what you want to keep will determine what other fish are compatible with your choice of fish. Compatibility charts are helpful and can be easily found on the internet. Keep in mind different fish have different requirements. Cold water fish like goldfish need unheated water while tropical fish like neon tetras need a heated water. Be sure you can provide whatever your fish may need to thrive. Your fish may not be happy if simple needs are not kept. Size matters, some fish can get pretty big, they seem small in the pet store but their adult size can be very large. It's good to know a little about the fish you're considering before you purchase it. I know this process may be difficult, but you will find the perfect type with plenty of research.

Fish compatibility chart

Step 3: So Many Filters...

Filtration is very important don't skimp on this. It's the biggest investment for your aquarium and can be the deciding factor of a successful aquarium.

As far as filtration goes there are a couple of main types to choose from: Hang on back/power filter, canister filter, internal power filter, under gravel filter, sponge filter, and wet/dry filter. Selecting a filter can be a daunting task, but it's all about preference and performance. People will argue about what's the absolute best filter. They'll tell you in order to be successful you have to get the one they recommend. I'm not saying don't listen to them, but research for yourself and come up with a decision based on what you want. You will be performing the maintenance on the filter not them. If you don't like how complicated it is or if it's a pain to maintain then don't purchase it. You're not going to want to mess with it or properly maintain it if you think its complicated or hard to maintain. Your maintenance should be enjoyable and easy not some complicated task you loathe doing.

Filters usually work with three types of filtration. Mechanical (filtration takes out the debris and particles in water), Biological filtration (takes care of the nasty deadly stuff in your aquarium water), and chemical filtration which is optional for the most part(removes odor and dissolved organics in your water).

You'll want to select a filter that filters your water at absolute minimum of 4 times per hour. Different fish have different bio loads which basically means they produce more waste such as goldfish or cichlids. Having more fish means more waste will be produced. If you plan on stocking your tank to max capacity you'll need to plan accordingly. I would shoot for higher filtration rates like 6 to even 10 times per hour. Like I said it depends what you plan to do. Some companies will advertise their filter for a certain size aquarium This is hit or miss because they usually label based on 4 cycles per hour. Follow the times an hour rule to be sure you're covered. For example, if you have a 30 gallon aquarium filtering that 6 times per hour will require 180 gallons per hour or gph to be filtered.

(size of aquarium)X(times needed filtered in an hour)=(gph needing filtered)


Your filter will need to filter 180 gph if you have a 30 gallon aquarium. Don't worry about over filtration it's always better to go bigger and have more than enough than to not have enough.

Lets talk a little more on the different types to help you decide:

Hang on back/power filters or aka HOB filters are probably the most common of all filters. These filters are known for their ease of use and excellent mechanical, biological, and chemical filtration. Most HOBs are accessible from the top making it easy to replace filters and accomplish maintenance. The downside to this type of filter is it may become clogged if not check for a while. Most of these types of filters are built with a bypass function so water will simply flow around the filter when clogged. So, even if you hear the filter running and the water flowing it may not be working, this can be disastrous to your fish. As long as you check it every so often this can be a very easy and reliable filter to own. Also these filters may make a trickling sound if water levels are low. They provide good surface water agitation which helps oxygenate the water. Some have water flow adjustment so you can adjust the water output. These make really good and popular filters for smaller aquariums.

Canister filters are powerhouses for filtration. Their high filtration rates make them a good choice for fish that produce a lot of waste and for larger aquariums. They provide superb mechanical, biological, and chemical filtration and at high gph rates. Depending on the brand these filters are also virtually silent. The only thing exposed in the tank is the intake tube and output tube. The tubes can be positioned in the tank to spray from one side and suck up from the other, which can circulate the tank pretty nicely. You can even attach a spray bar to spread the water output across the aquarium. The down side to these filters is complexity and maintenance. It can be a pain to maintain this type of filter, and often it's avoided because of this. Also, if the filter gasket fails or a hose line cracks (though not common or known to happen) your water will be relocated nicely on the floor. Depending on the size of your aquarium this can be a lot of water.

Internal power filters are what they sound like, filters that sit in the tank and filter the water. Similar to HOB filters these filters provide good mechanical, biological, and even chemical filtration. Internal filters are handy because they can be placed virtually anywhere in the tank, even near the bottom. This will providing good water flow over the substrate which can kick up waste for the filter to catch. They come in a variety of different sizes for different size aquariums. Smaller internal filters are usually powered by air and are a good choice for you guessed it, small aquariums. One downside to this type of filter is having to pull the whole filter unit out to change the filter material. This depends on the location in the aquarium and brand you buy.

Undergravel filters have been around for quite awhile. This type of filter, as the name implies, is underneath the gravel and uses the gravel as a biological filter. There are options for mechanical and chemical filtration but it's not common. It's usually driven by an air stone placed in the bottom of a tube attached to the base. It can also work from a power head attached to the top of the tube. If operated with an air stone air passes through the tube and pulls water through the gravel and up the tube with it. This circulates the water through the gravel and aquarium. If it's powered by a power head (which is basically an internal water pump) it will work in the same way just with a lot more circulation, and without the bubbles from the air stone. Although this was a popular method a short time ago, with the advances in technology this is no longer a preferred method of filtration. It's nearly impossible to keep the gravel clean because your beneficial bacteria is housed there. Almost any tank size can be fitted with this type of filtration. People still swear by this type of filtration but the choice is ultimately yours.

Sponge filters go unnoticed but are actually really good at mechanical and biological filtration. These filters are perfect for fry and betta tanks or anything that requires minimum water flow. Sponge filters are great backups to keep running while you're maintaining your main filter. They come in various sizes and are extremely cheap but don't let the price fool you it's an extremely effective type of filtration. Sponge filters are mainly ran off of air stones much in the same way as an under gravel filter works except instead of gravel a sponge is used. These can be placed on a powerhead or even on the intake tube on an existing filter. This makes them really versatile. Maintenance is fairly easy for a sponge filter. Just remove the filter and rinse in water pulled from the aquarium. The only downside is the inability to have chemical filtration and how unsightly it can be sitting in your tank.

Wet/dry filters are considered the ultimate in mechanical, biological, and chemical filtration. They are highly customizable and can even be crafted by someone who is handy. They are really popular in saltwater aquariums and gaining popularity in freshwater. They provide the perfect environment for the beneficial bacteria to thrive in. Wet/dry filters are named so because they expose the bacteria not only to water but to air. This is what canister can't do because they're completely sealed. Maintenance is virtually non existent you just need to rinse the filter media every so often. Wet/dry filters are usually placed under the aquarium in the cabinet to keep them out of sight. The only downside is complexity of setting up and cost. Most require you to have a plumbed aquarium which is basically a drain drilled into the aquarium.

Step 4: What Else You May Need...

I know went on the deep end there on filters, but I promise this part won't be as bad.

Remember to read all instructions and understand how everything operates before using any equipment. Also, make a drip loop for all your equipment to reduce the risk of electrical fire or shock. A drip loop is basically letting the cord hang lower than the outlet and equipment. If water happens to find its way on the cord it will drip off the loop at the bottom instead of your outlet or equipment.

If you bought a kit then you should have everything you need, if not here are some recommended/needed items:


The basic rule on heaters is 3 watts per gallon. Usually manufactures will put the appropriate size tank there heater is capable of heating. For coldwater fish this is not needed unless you live in an extremely cold environment. I recommend getting in internal thermometer. It is more accurate than a sicker one, and not as susceptible to temperature changes in the room.

Air pump
If you like the bubbling effect or if you have a filter that requires this then you're going to need an air pump and air stone don't forget a check valve. Check valves keep water from entering your pump if it's not operating.


This is important if you wish to keep live plants, you'll want quality lights so your plants can flourish. Pretty much your choices are fluorescent and LED's, stay away from incandescent bulbs. They both have their advantages and disadvantages and again research is important. Most fish look better under different color lighting so tailor your decision off that aspect.


Not completely necessary but extremely helpful. This is especially helpful when you have algae problems and you're not around to control the light schedule.

Gravel Vacuum and bucket

This is important, you'll be accomplishing a lot of water changes and this will become your friend.

Water test kit

I highly recommend a water test kit. This is vital to know when your tank is cycled. Not only that but you need to test water parameters every so often to make sure things are working as they should.

Water conditioner

This is extremely important to have! It basically dechlorinates and takes the heavy metals out the water making it safe for fish. Another option is to use reverse osmosis water.


An obvious one but an important one none the less.

Aquarium cleaner

This little magnetic guy will be a good friend for keeping your glass clean (it helps if you get one that floats).


You'll need something to catch your fish, be sure you get one big enough for your fish's adult size.

Step 5: Putting It All Together...

Alright now we are getting to the fun stuff. Setting up your aquarium, yay! Ok so first things first you need to decide on an overall theme for your aquarium. Like whether your want to have a natural look or have all kinds of crazy cool decorations. Maybe you want to create an underwater lost city. Go with something that expresses you but will also keep your fish happy at the same time. If you want a background go ahead and put it on or if you want paint the back of your aquarium nows a good time for that.

If you decide to paint the back of your tank be sure to use a small sponge roller and latex paint. You will not be able to get it in one coat it will take multiple coats and a lot of patience. Try to get an even coat as possible. Less is more in this case. It's easier to build upon layers than glop it on there and have gaps or thin areas where the paint didn't adhere to.

As far as substrate goes the rule of thumb is 1.5 to 2 pounds per gallon. Wash your substrate thoroughly, you'll thank yourself later. Place it in a large bucket and rise it with a hose mixing it thoroughly till the water is clear. This can take a while. Place your substrate in your tank in an even layer. You'll want about an inch or two of substrate. To create more depth you can make a hill with your substrate. Start from the front and work your way back so the front is thin working up to being thick in the back like in the picture above.

Place your decorations in a manner that is aesthetically pleasing. If you want look up the rule of thirds. It's a good thing to keep in mind when you setup your aquarium. I would talk about aquascaping and the rule of thirds but that would take a whole other instructable. To keep it simple know what angles your aquarium will be viewed from so it looks good from all those angles.

It's time to express yourself do what you think looks good most of all have fun.

Good Reads:

Rule of thirds


Step 6: Cycling Your Tank..

Your almost there! The last and most important step is cycling your tank. If you pull anything from this instructable it should be this step. I know your thinking what is cycling your tank? Why do I need to do it?

Let's begin with a brief introduction about the nitrogen cycle.

Fish produce ammonia as waste which is extremely toxic to fish. This will kill them or damage them for the rest of their short lived life. Luckily ammonia is converted to nitrite by nitrifying bacteria. But we are not out the clear yet. This, yes as you guessed it, is still toxic to fish. Mother Nature seems cruel right about now, but there is one last piece to the puzzle. Nitrite is then converted to nitrate by another type of nitrifying bacteria. This is not as toxic to fish but in large amounts, around 40 ppm, it can be. Do you get why its called cycling your tank now?

Ok now that you have a basic understanding of the nitrogen cycle we can dive into the process of cycling your tank. There are two ways to cycle your tank with and without fish. Either way you choose the process remains almost the same. Cycling takes a couple of minutes a day for one to four weeks. There is no exact time frame your tank will be completely cycled. Be patient during this time, it will eventually cycle and achieve a biological equilibrium. If you have a small tank under 10 gallons you may never achieve a biological equilibrium. This means your tank may never cycle. Smaller quantity of water equals instability with water parameters. To put it plainly things go wrong quicker in a smaller aquarium.

To start the cycling process you need to decide whether you want to do fish or fish less cycling. Be sure to fill your tank with treated dechlorinated water. Chlorine is put in water to kill bacteria and you're trying to grow it. I highly recommend purchasing a master water testing kit. The cycling process is impossible to track without it. To do fish less cycling you will need to find ammonia that has no dyes, perfumes, surfactants, or detergents. Ace hardware is a good place to find it. It's usually called janitorial strength ammonia. An easy way to check if it is safe is to shake the bottle. If it foams at the top you don't want this stuff in your aquarium.

If you start with fish start with very few fish and make sure they're hardy fish that you don't mind keeping in your aquarium.

Fish less cycle

To do a fish less cycle add a small amount of ammonia to your tank to achieve 4 ppm of ammonia. Wait 20 to 25 minutes for it to circulate, then test again. You should maintain a constant ammonia level of 4 ppm during the entire process of cycling. If you over due it just do a small water change to get it back down. Test ammonia everyday or every other day and wait for the ammonia to drop. Once it starts to drop it is a sign your first colony of nitrifying bacteria has started to establish itself. Start testing for nitrites and cut back on testing for ammonia. You're looking for an increase in nitrites. Once your nitrites spike it will slowly start going back down. This is a sign your second colony of nitrifying bacteria is establishing itself. Start testing for nitrates and stop testing for nitrites. You will see a steady increase in nitrates. This is a sign that your tank is almost fully cycled. Once your aquarium is converting ammonia to nitrates overnight then congratulations you are fully cycled. Complete a 50% water change and your tank is ready for fish. If you plan on getting your fish at a later time keep feeding your bacteria with about 2 ppm of ammonia till you do. Stop dosing ammonia in the tank a day before you get your fish and do a water change.

Cycle with fish

To cycle with fish choose fish that you intend to keep that are hearty. Don't listen to the person working at the fish store when he/she says use feeder fish. These can harbor parasites and spell disaster once you add your other fish. Don't start with any other fish than the one you want to keep. It only takes about 1-2 fish for a small aquarium and 3-5 for larger aquariums. During this process feed your fish sparingly. Any left over food will contribute to the production of ammonia. More food means fish will produce more waste, which causes more ammonia. Using an ammonia detoxifying additive (usually called ammo-lock) will benefit your fish during this process. It detoxifies the ammonia making it more safe for fish but does not remove it. You still need to do water changes to get rid of the ammonia. You will need to test for ammonia each day and do a 25-50% water change every day to keep ammonia levels low to non existent. Yes, it may take longer for it to cycle but your fish will thank you in the end. Once your ammonia levels diminish start testing for nitrites and stop testing for ammonia, keep up the water changes. Once your nitrites peak than start to fall test for nitrates and stop testing for nitrites. Yes, keep up the water changes it's almost over. One day soon your test will show no ammonia, no nitrites, and high amount of nitrates congratulations your tank is cycled. Keep watching a couple of days after and make sure the ammonia and nitrite levels stay at zero or trace amounts.

Once your tank is cycled you are ready to slowly add more fish. As you add fish your tank has to adjust to the higher bio load this is why you have to add fish slowly. To add fish float the bag on top of the aquarium for an hour or so. Let some water from the tank into the bag to help acclimate the fish to the difference in water parameters. I would advise against pouring the bag of water into the tank. You don't know what the water could have in it. It's a good idea to quarantine fish in a separate smaller tank in case the fish is harboring parasites. You usually want to wait a week to see how the fish is doing and treat it for any signs of ick or other life threatening conditions. Its easier and cheaper to treat the one fish in a quarantine tank instead of contaminating your nicely setup aquarium. Quarantine tanks are usually small tanks with a sponge filter and usually have no decorations.

Step 7: Wait, What About Maintenance?...

To keep your fish happy just accomplish your maintenance for your filter outlined in your manual. Complete weekly or bi weekly water changes to keep those nitrate levels below 40 ppm. If you do a weekly water change replace 10-15% of your water. If you do a bi-weekly water change replace 20-25% of your water. When you are completing your water changes vacuum your substrate and get rid of any algae buildup on the glass. It's really not much to maintain after everything is established. It may take 10 to 15 minutes each week or two weeks to complete.

Other than that enjoy the fruits of your labor!

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    5 years ago

    Great source of very valuable information, especially for someone just getting into the idea of aquascaping. I love this form of art!!! Thank you for taking the time!

    nice post Thanks for that...


    7 years ago on Introduction

    Nicely done! Thanks for sharing this great guide.


    Reply 7 years ago on Introduction

    Thank you and thanks for all the help.


    7 years ago on Introduction

    Nice one mate ! Decent time invested in writing this ible.