Hello and welcome to the UK Planted Aquarium and Aquascaping FAQ. This was written by the group moderator, Tom Page, to answer most of the commonly asked questions we see on a weekly basis in the group.
What this guide is: A quick reference guide for those who want to know the topline answers, or most commonly held opinions, on some of the most frequently asked questions around planted aquariums and aquascaping.
What this guide is not: An in-depth guide to any of the below subjects that takes into account every possible answer to a question or product within a category.
1. General
What temperature should I keep my tank at?
The welfare of your fish is the most important consideration, bar none. So whatever temperature they are most comfortable at. Be aware that hotter temperatures generally encourage faster growth of everything, including algae, and most plants do not enjoy very high temperatures (e.g. 28c). Most aquascapers keep their tanks at 21–24c.
What size water changes should I do?
Generally speaking, most aquascapers will do large, frequent water changes of 50% to 80% once or even twice per week. This helps remove waste organics produced by fish and plants, any excess nutrients and is a good time to clean the glass, filter and the substrate.
I’ve heard I need to cycle my tank before adding fish. Is my tank cycled?
Your tank is cycled when you have been adding household ammonia daily, and after 24 hours, no nitrite or ammonia can be detected by a test kit. This usually takes at least 3-4 weeks. It can be sped up by adding filter media containing beneficial bacteria from a existing filter.
Where should I put my tank?
To prevent algae, it is important to control the amount of light hitting your tank. That includes sunlight. Therefore try and put it somewhere shady in your house.
2. Consumables
Should I buy a test kit? Which one?
Yes. You need to monitor water quality. NT Labs “Aquarium Lab” test kit costs about £25 and has everything you need. Also it makes you feel like a real scientist.
What are the best fertilisers to use?
The two most commonly used premixed fertilisers are TNC Complete or Tropica Specialised. If your water has high nitrates out of the tap, you can try TNC Lite or Tropica Premium.
However, it is around 10x cheaper to buy it dry and just add your own water. Aquariumplantfood sell a “starter ” kit. It is not hard. If you can make a pot noodle, you can mix your own ferts.
What is the best water conditioner to buy?
Seachem Safe. It is a powder and is around 10x cheaper than pre-mixed water conditioners, where you are mostly paying for water. 250g treats 100,000 litres of water. That is a lot of water changes.
What fish food should I buy?
That depends on what your fish like. There are so many high-quality fish foods available out there, it’s hard to go wrong. But the best thing to do is to google your fish and see what other people are feeding them. The important thing is not to overfeed your fish.
3. Equipment
CO2
Do I need CO2?
Do you need ice cream on a hot day? Not necessarily, but it makes everything better. Carbon makes up more than 40% of a plants biomass, so it’s vitally important that plants have access to it. It exists within the water of your aquarium anyway at low levels, that will be okay for very easy plants (Moss, Anubias, Bucephalandra, Java Fern). However, injecting CO2 will mean faster, lusher growth, and healthier plants overall. This is a huge factor in reducing the risk of algae, as the healthy plants outcompete the algae. Injecting CO2 will also let you try out a much, much larger variety of plants.
What CO2 kit should I buy?
There is one obvious recommendation that is suitable for 90% of shoppers. The CO2 Art Pro SE Complete Kit. It contains everything you need (minus CO2) to get started. Do not pay full price however. CO2 Art will almost always email you a ‘money off’ voucher. To get this, register on the CO2 Art website, add the kit to your basket, but don’t check out. Or you can use the “wheel of fortune” that sometimes pops up on their website.
Where do I get my CO2 from?
Lots of people sell old fire extinguishers on Gumtree, Facebook, etc. However, you can also buy new or reconditioned canisters cheaply on ebay. Alternatively, local fire safety, welding shops or air rifle shops may refill cannisters for you. You should aim to pay between £7 and £15 for 2kg — but rates vary significantly depending on where you go. New cannisters cost a lot more.
What about CO2 diffusers?
There are three main types of diffuser.
Tank diffusers, such as atomisers, sit in the tank and are connected via a small tube to the CO2 regulator. These are good for smaller tanks up to around 100l. They should be installed somewhere that maximises the time the CO2 bubbles spend in the water column, such as under the outflow.
Inline diffusers are installed along the tube that connects a cannister filter outflow to the Lily Pipe outflow. They are good for larger tanks as they provide better CO2 diffusion than in tank diffusers.
CO2 reactors are the final type of diffuser and are recommended for tanks of more than 300l. They do reduce flow from the filter, but do have the advantage of completely dissolving the CO2, so you don’t have the “carbonated drink” effect of seeing lots of little bubbles.
Is liquid carbon a good alternative to CO2?
No. It releases very little bioavailable carbon that plants can actually use. However, it can be spot dosed with a syringe to kill algae — but beware, the main active ingredient is toxic and you should try to minimise its use in your aquarium.
When should I turn on my CO2?
Have it on a timer that goes on about an hour before your lights turn on and off an hour before they turn off.
How many bubbles per second should I run?
Forget bubbles per second. It is a useless metric. Get a drop checker and some drop checker solution. When the solution turns lime green you’re CO2 levels are spot on. Yellow = too much and Dark Green/Blue = too little.
Filters
Over filtertration is always better. You will see clearer water and have greater capacity to remove any harmful nitrate or ammonia caused by fish waste, plant waste and leftover fish food that is rotting.
Don’t believe what the manufacturers tell you regarding capacity — realistically it is always about half the maximum number they give. For example, for a 250l tank you would buy a Oase Biomaster 600 Thermo, which Oase say has a 600l capacity.
For small tanks, you might choose an in tank filter such as the Aquel Mini Pat Filter. But for larger tanks (50l or more), you might be better off with an external cannister-style filter. This means you can reduce the amount of equipment in your tank.
Popular external filters are the Oase Biomaster Thermo Range, the Fluval x07 Range and Eheims Experience/Professional Range.
Additional note: for bigger tanks, it is very common for aquascapers to use two filters. This not only helps with filtratation, but also with overall flow of water in the tank.
What about flow?
Recently, flow is being seen as more and more important in a tank. It’s all very well injecting CO2 and adding fertiliser, but if it doesn’t get moved around the tank to the various plants that need it, then it’s not going to help. The use of a second filter or a powerhead can help with this. A sign of good flow is that you see plants slowly moving as the water moves around the tank. It should not look like a news reporter giving an interview in a hurricane, however.
It’s worth noting: some fish, such as bettas, do not like high flow environments. Do your research.
What’s this about Lily Pipes?
Lily Pipes are the intake and outtake of your cannister filter. They can be made of stainless steel or glass. Beware, the glass ones are very easy to break but are almost invisible. Stainless steel is a good choice when new and, since they hide the dirt, require less cleaning to keep them looking perfect (though they still need the same amount of cleaning to keep them… well, clean).
What size Lily Pipes and hose do I need?
There are two commonly used sizes: 12/15 and 16/22. The first number is the inside diameter of the pipe in mm, the second is the outside diameter in mm. Generally smaller filter require 12/15 and bigger filters require 16/22.
What filter media should I use?
In a planted tank, it is worth noting that the plants themselves do an excellent job of assisting your filter, so filter media isn’t as important as it might be in a fish-only aquarium. That said, as above, more filtration is always better. Popular filter media includes Alphagrog, Biohome Ultimate and Seachem Matrix, but many people have also had success using regular ceramic rings or even crushed lava rock. Just make sure you have enough media, do not over stock with fish, ensure your plants are healthy and test your water regularly.
Should I use carbon in my filter?
Carbon is generally used to improve water clarity as it filters out a lot of organic compounds. However, it “runs out” and has to be regularly replaced. If you have good enough filtration and regularly clean your filter, you should not need it. Seachem Purigen does the same thing as carbon but can be “recharged”.
Note: If you are dosing medications, then remove carbon/purigen from your filter as it will filter out the medicine.
4. Lights and lighting
What lights should I buy?
The two considerations are: your budget and your requirements.
If you have easy-to-grow plants, in a small, shallow tank, then you only need a small amount of light. If you have a large, deep tank and harder plants, then you’ll need more powerful lights. It is hard to make exact recommendations for different setups, but as a rule of thumb: 1w per 1l of tank capacity = high lighting, and 0.3w per 1l of tank capacity = low lighting. Cost goes up the bigger the light.
Some good budget lights are Lumini Asta F20, Aquel’s “Leddy” range, Twinstar’s “B Series”, Nicrews “Planted” range.
Some good mid-range lights: Fluval’s Planted range, Chihiros A series, Twinstar’s “E series”.
Some high-end lights: Kessil A160We or A360X, Twinstar’s “S Series”, Chihiro’s “WRGB VIVID” and “WRGB II” range, or if you have money to burn, ADA’s “Solar RGB”.
How long should I leave my lights on?
Between 6 and 8 hours for most people. Less light reduces your risk of algae, longer can promote faster plant growth. If your lights aren’t adjustable in terms of intensity and just lower the time they’re on per day.
What intensity should I have my lights?
Broadly speaking, lower if you are not running CO2, adding fertiliser, or if your tank is new and doesn’t have a lot of plants. Light intensity can be slowly increased as plants grow in. Often it is good to run at 50% intensity for the first 4 weeks of a new tank.
What tank should I buy?
Most aquascapers want their tank to be easily accessible and use shallow, rimless tanks. These allow you to easily clean and maintain your scape. The use of Optiwhite glass is highly recommended so you can see fish and plants in their truest colours, rather than with the greeny/blue tint you get with normal “float” glass.
Some of the most popular manufacturers are Evolution Aqua, ADA, All Pond Solutions, Aquariums 4 Life and NACD.
Do I need an airstone?
An airstone helps with oxygenation of the water, which is essential for happy fish. Do you know what else helps with oxgyenation? Plants — which give off oxygen when photosynthesising. Therefore, most aquascapers and planted tank enthusiasts do not run an airstone. You could one run at night, for example when the plants are not photosynthesising, but again, it is not a necessity.
5. Water chemistry
I have hard water, what does that mean?
Many people around the UK have hard water. The main thing you need to know, is that when choosing fish, you should try and choose fish that suit your water chemistry. Plants are relatively adaptable, and although most prefer softer water, with good lighting, fertilisation and substrate, they will grow in most water. This is not a deep discussion of hard or soft water, but if you want to read more you should consult this guide.
One more point of note: generally hard water contains less CO2 and, as such, plants in hard water will benefit greatly from CO2 injection.
Is there anything I can do to soften it?
Yes, you can buy an RO unit which removes all the impurities and dissolved solids, and then remineralise it yourself. If you are just starting out though, it is recommended to just use tap water with a water conditioner, and choose fish that are suitable.
I have high nitrates. What should I do?
Have you tested your tap water? A lot of tap water in the UK contains high nitrates, so if you are also dosing fertiliser on top it often leads to very high nitrate levels. Nitrates are not as harmful to fish as nitrite or ammonia, but will contribute to overall health decline over time.
The best solution to this issue is to add more plants, especially floating plants such as Frogbit or Salvinia Auriculata which will feed heavily on the excess nitrates (they are not limited by CO2 as they have access to it in the air). Additionally, either move to a pre-mixed fertiliser that contains no nitrate, such as TNC Lite or Tropica Premium. Or even better, start mixing your own fertiliser and don’t add any nitrate (see the fertiliser section)
I have soft water.
Okay, no need to boast.
6. Substrate
What types of substrate should I use?
For success you should use a substrate designed for plants. Plant substrates are able to absorb nutrients from the water column and hold them, making them available for plant roots to absorb. There are two grain sizes to most plant substrates: “normal” and “powder”. Powder is best used when you are planting smaller plants or carpets as the small roots can more easily grip it.
The most commonly used plant substrates are Tropica Aquraium Soil, Prodibio, Aquagrowth Soil and ADA Amazonia.
The most commonly used substrate powders are Prodibio Aquashrimp Powder and Tropica Powder.
Can I plant in sand?
Most plants will not grow well in sand. It is an inert substrate (does not hold fertilisers, etc) and the very small grain size often leads to anaerobic conditions which are bad for the plant roots.
7. Hardscape
What rocks should I buy?
The choice is up to you. Go for something you like the look of and can afford. There are so many types out there today.
For beginners, Seiryu Stone is a popular grey-coloured rock, with lots of interesting textures, and is commonly available and not too expensive. Black Lava Rock is a very easy rock to start with. It’s cheap and easy to attach epiphyte plants (plants that grow on hardscape).
How many kilos of rock should I buy?
It depends on the type of rock, because they have different densities. Lava Rock is light, so you don’t need as much to fill a tank. Frodo Stone is very dense and heavy, so you need to buy a lot to fill your tank. A general rule of thumb is 20kg per 50l of tank space — but it completely depends on the type of scape you are going for. For very rock-heavy “mountain” style scapes, you will need a lot. For jungle-style scapes, you might not need as much because wood may be the focus.
What wood should I buy?
Up to you — buy whatever you like the look of! A lot of new aquascapers use Red Moor root as it is readily available at most shops. Aquascaping specialist stores (mentioned below) have far greater choices.
Additional point of note: some wood, such as bogwood, can release a lot of “tannins” into the water, turning it a tea-like colour. To limit this, it’s best to leave the wood to stand in a bucket of water for a few weeks before it goes into your tank. You can also use Seachem Purigen or carbon in your filter, which will remove the tannins.
What is this slime growing on my wood?
Gross! Don’t worry, that is biofilm. Bacteria in the tank are consuming the sugars in the wood and producing it. Shrimp and snails love to eat it, and it will eventually disappear. It can be scraped off if you don’t like the look of it.
8. Plants
What plants should I put where?
Generally speaking, you should plant your smallest plants at the front and your biggest at the back of the tank. This helps create “layers” of perspective. When considering what to buy, always look at the size your plants will grow to. For smaller tanks, aquascapers often use small-leaved plants, which give the impression that the tank is much larger.
Carpeting plants are usually small and are often placed right at the front of the tank.
Be aware, that slow-growing plants should not be placed in the areas of the tank that receive the highest levels of lighting, as they will likely develop algae.
What plants do you recommend for a low-tech tank?
Most mosses, Java Fern (microsorum), Anubias, Bucephalandra and most plants from Tropica’s “easy” category can be used
What is this “epiphyte” plant people keep mentioning?
It is simply a plant that does not grow in a substrate and instead should be attached to either rock or wood. This can be done using either superglue or black cotton thread.
What plants grow well at higher temperatures?
If you are keeping warm water fish such as Blue Rams, Discus or Betta fish, you will need to choose plants that cope well with higher temperatures. Commonly used plants in these tanks include Amazon Swords, Crypts, Anubias, Saggiteria, Valliserias, Java Ferns and Nymphaea. Also common mosses such as Java Moss may work well.
How do I get my plants to turn red?
Choose plants that turn red in the first place and then trim them back and replant the stems, increase lighting intensity (but not so much that you get algae) and lower the nitrates in your water. Some nice red plants are Limnophilia Hippuroides, Ludwigia Mini Red, Alternanthera Reineckii Mini and Rotala H’Ra.
I have algae. Help?
Algae is the Darth Vader of fish tanks. Deep inside, it’s not inherently bad, but it does like to take over and strangle the other plants in your tank. There are lots of different types of algae, all caused by different things, and addressing all of them is outside of the scope of this guide. Generally though, to minimise algae you should aim to have good levels of flow, not too much light, consistent and correct levels of CO2, enough fertiliser for your plants to remain healthy, lower temperatures, regular tank and filter cleaning, and large, frequent water changes.
For more information on the above and to deal with specific types of algae, you should check out the below resources:
How do I use liquid carbon or hydrogen peroxide to kill algae?
Buy a syringe. Turn off your filter. Leave it one minute so the water has stopped moving. Then squeeze small amounts of either of the above over affected areas/plants. Leave it for 10 minutes, then turn your filter back on. Repeat daily until the issue is gone. Neither of the above products should be used in place of proper maintenance and dialing the correct CO2 and lighting levels in.
9. Aquascaping technique
How do I choose a layout?
Very, very broadly speaking, there are three styles.
Triangular — where the scape start high on one side then dips.
U-shaped — where the scape has hardscape on either side with a gap in the middle.
Island style — where the hardscape is placed in the centre of the tank with open space around it.
The best thing to do is find a scape in a picture that you like and try to recreate it. It’s a good idea to keep things as simple as possible to start with. Don’t be concerned if your version doesn’t look as good as the one in the picture. Practice makes perfect.
Is there one tip that would help me build a better scape?
Yes. Whatever style of scape you choose, have your focal point one third of the way along the length of your tank. Your focal point could be a large rock, a piece of wood, a plant, or even better, a combination.
Which YouTubers do your recommend I watch to learn about technique?
George Farmer, Green Aqua, Tank Tested, MD Fishtanks, The Cinescaper
I’ve got sand and my substrate keeps running onto it. What should I do?
To prevent this, stuff the gaps between the rocks with filter floss. If you do not have rocks between your sand and your substrate, they will always mix.
10. Fish
What fish should I buy?
This is out of scope for this guide, but do your research before you go shopping and don’t always believe what the employees of your local fish shop tell you. Especially if your local fish store is a Pets At Home (or Petco if you are in the US). They are just there to make a sale and often do not care about fish health, fish happiness or your tank.
Most aquascapers tend to use small/nano fish because their small size can add to the look of scale of the aquascaper itself and they often shoal beautifully.
Also remember that fish grow, sometimes very large, and overstocking your tank is almost certain to cause algae issues.
Can I keep cherry shrimp with my fish?
Most nano and small fish can be kept with cherry shrimp. They may eat some babies, but generally the shrimp will do okay. Larger fish will make cherry shrimp a very expensive snack.
How many fish should I buy?
That depends on the size of your tank, but as above, overstocking your tank is a recipe for algae.
I think I have Planaria!
You probably don’t. It is more likely you have Rhabdocoella, which is totally harmless. Google pics of both. Planaria have triangular heads, Rhabdocoella do not. If you do have Planaria, then dose No Planaria. And yes, it is safe for shrimp and snails.
Which snails should I get?
Snails are great at eating some types of algae and general cleanup. Most often people recommend adding Nerite Snails as they don’t breed in fresh water. They do however lay white eggs on hardscape. Be aware that Ramshorn or Mystery snails will breed like rabbits, and if you over feed, they can and will take over your tank. That said, they will certainly keep it clean!
Can I use fish and invertebrates as a “cleanup crew” or algae eaters?
Yes, some fish such as Siamese Algae Eater (SAE), Otocinclus, snails and shrimp will help keep your tank clean by eating leftover food, algae and detritus. However, they are in no way a replacement for water changes, cleaning your filter, and/or vacuuming your substrate. Amano shrimp and snails are generally the best option as the do not significantly add to the bioload of the tank and are also very efficient.
11. Shops
Where should I buy all this stuff from?
Almost everything on this list can be bought from the UK’s main aquascaping stores — including the group sponsor Scaped Nature. The other highly recommended shops are Riverwood Aquatics, Aquarium Gardens and Horizon Aquatics. Alternatively, Pro Shrimp has a great range of plants and equipment, though do not stock hardscape.
