20 gallon tank setup

I am starting to setup my 20 gallon tank. Does it matter where I put my heater. I have a cutout in the cover that places it next to the pump.

It's good to have it close to the filter, where the water movement will spread the warmth.

Good to know, thanks

I'm setting up my new aquarium and I was told to use ammonia to help it along. Is it the ammonia that you buy in the grocery store or does it have to be a special ammonia.

Ah, the famous fishless cycle. It's a valid chemistry experiment if you are into reading ammonia tests and such. It is not necessary, or especially better than a slow, well planned cycle, but it is in right now.
To do this you need a tank with no fish, pure ammonia and 30 bucks worth of testing kits.
You could also plant the tank, stock very lightly, be patient and ignore the fishless cycle.

Well I'm on a pension and limited as far as money so I'm trying to do this as cheap as possible. I started getting into fish last March and had a 10 gallon aquarium and knew nothing about this nitrogen cycling. I bought some fish at Big Al's and asked them at the store about how to setup a tank and was told nothing about this cycling. I was told what fish to buy and what food to give them and went from there. The only test kits I was told I needed was PH and ammonia, which I have. Now that I moved and got a 20 gallon tank and starting over I decided to get on this forum and see how the experts do it. WOW what an eye opener. People are telling me know that I need to test for Nitrites and Nitrates and It seems that those kits are expensive. Plus the ammonia that you mentioned, never heard of that before. I had planned when I got moved to put water in the tank, add fish food for a couple of weeks until I can afford some fish and go from there.

Hey werwer2016.  Congratulations on your new setup!


Be careful when taking advice from Fish Store employees.  In my experience it's bad advice more often than not.  Like the pH and ammonia test kits.  While they may help, you certainly don't NEED them. As a matter of fact you don't need any test kits at all. You can take a small baggie or cup of water to petsmart and they will do basic testing for you that will tell if your tank is cycled or not.



Some people may disagree but I'm a huge fan of using zebra danios to cycle my tanks.  They are super hardy and can easily survive the nitrogen cycle.

Right now I just have water in my tank and have added a bacteria supplement, stress coat and clarity. I hope to add fish the 1st of November. So do I need to get a Nitrite and Nitrate test kit. I have been looking at them and they seem to be expensive. I also have to get gravel.

A general explanation of the nitrogen cycle.
A quick note, some may argue that the cycle additive is snake oil & does not work etc., but i suspect that is the product you have & might as well use it, nothing to loose.
https://www.youtube.com/watch?v=Rnnuy-f_r6E

Another expalanation
https://www.youtube.com/watch?v=es7spyo5RJ4

Thanks f or the video's

werwer2016 wrote:Right now I just have water in my tank and have added a bacteria supplement, stress coat and clarity. I hope to add fish the 1st of November. So do I need to get a Nitrite and Nitrate test kit. I have been looking at them and they seem to be expensive. I also have to get gravel.

If making a trip to the local fish store is not a problem for you then I'd skip buying the test kits and simply take a water sample into the store weekly which they will test for free and be able to tell you if your aquarium is cycled. I haven't owned any test kits for the past 6 years.

Now if the store is not close nor easy for you to get to then you may want to invest in some test kits for yourself.


also a tip for saving money is that you can source gravel or sand from landscaping supply places for waaaaaaaaaaay cheaper than your local fish store.

Thanks for the tips.

I'm thinking that instead of using gravel to use pool sand. I've read that people say that Cory catfish prefer sand versus gravel and that it is easier to clean. Is there any other fish that I can add with the cories. I have a 20 gallon high tank.

A school of tetras would make great tank mates for corydoras. They usually have similar water requirements.

How many tetra's and Cory fish do you think I can put in a 20 gallon high tank.

That really depends on the type of tetra you decide to go with. Some are quite a bit bigger than others.

They used to say 1 inch of fish per gallon as a baseline however I'm not sure if that's still considered the standard. So if the cories were to grow 2 inches you can fit 10 fully grown cories in there.

The old one inch per gallon was a pet shop sales formula for fish the weight of neons. A Cory is a lot heavier, and is therefore a heavier bioload.
When you think of it, there just can't be a 'rule of thumb' like that. Every species is different, and has different needs. Every tank varies, with filtration, temperature, etc. Every aquarist does different maintenance.

In my tanks, I'd have 6 Corys in a 20, with very little else in there. A planted (!!!), well filtered 20 getting 30% water changes every week could have 12 cardinals, but only 4 serpae. There's more to the fish than bioload - territorial behavior, social structure etc also kick in as factors.

Even a few years ago, an unplanted tank was seen as just wrong. Now, they are the pet shop norm, with plastic plants on a big comeback. A bare, sterile tank (even with a working filtration cycle) is a poor environment that supports a lot less life than a complex one. There's a lot to look at in all of this.

Thanks to everyone for the help.

Yes I thought that might be the case with the inch per gallon rule. People seem to have wised up over the past few years.

8 1-inch cardinals is definitely no the same bioload as 1 8-inch oscar. Or 1 8-inch goldie.

Well I'm still trying to decide what to put into my tank. Can you put more than one Beta fish in a 20 gallon tank. I know you can't put two males together.

werwer2016 wrote:Well I'm still trying to decide what to put into my tank. Can you put more than one Beta fish in a 20 gallon tank. I know you can't put two males together.

No worries friend, take your time. Do some searching around and find what fish are fascinating to you. It sucks because there are so many choices and we can't have every species we want. I never kept betas before so sorry I can't give you any advice on that.

Might I recommend trying a species tank? Meaning only 1 type of fish. Perhaps ~15 small tetras? Or 10 or so barbs? I've had better luck with barbs than tetras in the past, they seem to be a quite a bit more hardy.

werwer2016 wrote:Well I'm still trying to decide what to put into my tank. Can you put more than one Beta fish in a 20 gallon tank. I know you can't put two males together.

It will depend on the space available, and the temperament. Betta is just a genus (the common ones seen in LFS are Betta splendens), and there are many species. Generally people will keep splendens males apart. There are a number of species that can be kept peacefully (at least relatively) together. I have a pair of Betta simplex together right now (along with a number of other fish) and things go smoothly.

Thanks again for the help.

waterbearr wrote:

werwer2016 wrote:Right now I just have water in my tank and have added a bacteria supplement, stress coat and clarity. I hope to add fish the 1st of November. So do I need to get a Nitrite and Nitrate test kit. I have been looking at them and they seem to be expensive. I also have to get gravel.

If making a trip to the local fish store is not a problem for you then I'd skip buying the test kits and simply take a water sample into the store weekly which they will test for free and be able to tell you if your aquarium is cycled.  I haven't owned any test kits for the past 6 years.

Now if the store is not close nor easy for you to get to then you may want to invest in some test kits for yourself.


also a tip for saving money is that you can source gravel or sand from landscaping supply places for waaaaaaaaaaay cheaper than your local fish store.

I live in Fort Erie and after checking around the best that I can determine is that the closest fish store is PetSmart in Niagara Falls half hour away. I do have a PH and Ammonia test kit but don't have the money to put out for a kit for Nitrite and Nitrate. So I'll do the best I can with what I have now. This forum sure has opened my eyes a lot more to keeping fish than I expected. Thanks to everyone for the help. I'm hoping the 1st of November to get my gravel and fish.