Stocking a 20 gallon aquarium

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Waterfins

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My boyfriend is planning on setting up a 20 gallon long soon and doesn't really know what he wants in it. So I'm here to ask if anyone knows fish that thrive in a 20 gallon aquarium.

Note: The aquarium is NOT set up yet so please don't ask for the PH of my water or something similar to that. I can adjust those things for the needs of the fish I plan to get (crushed coral, driftwood, ect.). I ONLY WANT IDEAS!!! so I can set it up appropriately and know my options.

If you have other information such as compatible plants, what fish would work best with other fish then I would much appreciate that. Thank you.

(but if you must know my tapwater PH, it usually is around 6.5 - 7.0 and the hardness is around 30 mg/L (ppm) )
 
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Is this your first tank?

An option
1 pair of German Blue Rams
10-15cardinal tetras

Stocking:
Add 6 cardinal tetras, add plants if you want; wait a week
Add 4-9 cardinal tetras, add more plants
Wait two weeks
Add German blue rams, Add either 1 male 2 females or 2 females.

German Blue Rams need weekly water changes like every fish but they can die if neglected for too long. Feeding, feed then various frozen foods if you can, bloodworms and brine shrimp and a quality flake food.

Also if you like dwarf gouramis go with
1 dwarf gourami
6 lemon tetras
6 cardinal tetras
6 corydoras: pretty much any, if you want names, juli , peppered, albino, and try not to mix the corydoras just stay with same species.
Plants: Java Moss, Anubias, Cryptocorne any. Stay away from red plants unless you want to dose iron which isn't bad but is just another thing to purchase. You will need to get rootabs for the crypt and anubias.

To stock:

Add 6 lemon tetras and add plants if you want; wait a week
Add 6 cardinal tetras; wait a week
Add 6 corydoras; wait a week
Add dwarf gourami

Sent from my iPhone using Tapatalk
 
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Corydoras are great! I have sterbai cories and theyre so active and funny to watch..

Id say 6 cories for the bottom feeders - so for this you need a fine sand substrate.

I love the little non fun nipping barbs. Playful active fish. My cherry barbs always come and say hello at the front of the tank.

As im slowly finding with my tank, if you get fish that require a good size group of each species then youre going to want as many of them as possible.
 
I strongly recommend that you ascertain the water parameters of your source water (the tap water where this tank will be located). Without knowing these, we cannot realistically suggest suitable fish. Changing parameters is not as easy as it may seem. The pH is important, but of more importance is the GH (general hardness), and you should find out the KH (carbonate hardness or Alkalinity) as this works to prevent pH fluctuations. Any attempt to change the pH will usually fail if the GH/KH are significant. These are interconnected.

You don't need to set up the tank for this. The parameters of the source water are what you/we need to know, and you should be able to find these out from the municipal water authority. Most have a website with water data posted, or they can tell you.

Byron.
 
I strongly recommend that you ascertain the water parameters of your source water (the tap water where this tank will be located). Without knowing these, we cannot realistically suggest suitable fish. Changing parameters is not as easy as it may seem. The pH is important, but of more importance is the GH (general hardness), and you should find out the KH (carbonate hardness or Alkalinity) as this works to prevent pH fluctuations. Any attempt to change the pH will usually fail if the GH/KH are significant. These are interconnected.

You don't need to set up the tank for this. The parameters of the source water are what you/we need to know, and you should be able to find these out from the municipal water authority. Most have a website with water data posted, or they can tell you.

Byron.

30 mg/L (ppm) is where my tap water is at
 
30 mg/L (ppm) is where my tap water is at

I went back to review before responding, and saw this was mentioned in post #1, sorry I missed it.

So, that is very soft water (my tap is even softer, around 7 ppm) and you thus have many options for a 20g long. Stay with smallish fish; these always look better in smaller tanks, and you can have more fish for the space, which makes a more interesting aquarium in the end. Plants would be advisable, but you have a couple options.

You could do a natural aquascape from regions that have very soft water, such as South America or SE Asia. Use wood, lots of wood, as chunks representing logs, tree roots, tree stumps (vertical straight chunks of wood are ideal for this), etc, and branches if you can find some. Sand substrate, darkish; I use Quikrete Play Sand which you can get at Lowe's and Home Depot for about $7 a 25kg bag, which is more than enough for this tank (it is helpful to have spare down the road). Collect some dead leaves now in the autumn; oak, maple, beech work well, generally any hardwood that is deciduous is safe. Collect them from the ground after they fall naturally, in an area free of possible pollution. Lay them out to dry, rinse them first if you like; avoid any with bird droppings. When they dry, store them in a plastic bag and add a few as needed. Once they waterlog they will sink and you can lay them over parts of the sand for a very authentic aquascape. Here, plants would be confined to floating only, and a good covering would dim the light and make the fish sparkle.

Alternatively, some moderate-light plants can work, like the pygmy chain sword. Floating plants again, fewer to allow more light through.

If you want more SE Asian, swamp or pond/ditch-look, again sand, lots of wood, floating plants. Some substrate-rooted plants that have surface leaves work well here, like the Tiger Lotus varieties, and Aponogeton. Floating Water Sprite is ideal.

Thinking of fish ideas, for the SA tank there are pencilfish, some of which are very peaceful, others less so. Nannostomus marginatus (the lovely dwarf pencil), N. mortenthaleri (Coral Red, a real beauty) or N. rubrocaudatus (very similar) one of these in a group of 9-12. N. eques swims at an angle is is very peaceful, a group of 8-10. Hyphessobrycopn amandae (Ember Tetra) in a group of 9-12 would add an orangish-red colour. One of the dwarf cory species, in a group of 9-12 (Corydoras pygmaeus, C. hastatus, C. habrosus). Not all of these together, but they are species that will work here.

For SE Asian, there are the small-sized gourami species, like the sparkling pygmy, Eyespot, Licorice. The dwarf rasbora in the genus Boraras are perfect tankmates. Authentic substrate fish are more difficult, there are a couple of smaller loach species that are peaceful enough.

You don't want much filtration in any of the above, a simple dual sponge filter.

Byron.
 

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