Setting Up New 20G Tank, Don't Know What To But For It

[AJNOZ]

So I am looking to setup a new 20g tank, instead of the 10 gallon tank that I had originally planned.  This was due to my realization that I have fish that like larger tanks and it will give me room to grow.
 
I will be keeping my original 5g tank up and running as it is, however I'm unsure of what I'll need to buy along with the 20g tank.  While I have had smaller tanks and can keep them going well (3-5g) I've never taken on such a large tank.  On a sad note my oto catfish recently passed most likely due to age b/c the thing loved my moss (algae) balls and didn't exhibit any starvation symptoms.
 
I know I'll need the following:
 

• 20g tank (obvious)
• 20g hood
  I am putting this in a place that gets some sunlight so I'll need a hood with a light apparatus, but IDK which type (led, incandescent, or fluorescent, but I know I'll need something for the plants)

[*]Filter

• Not sure if I should get a wheel, sponge, but I'd like a 3 stage filter if possible

[*]Heater
[*]Thermometer
[*]gravel

• I normally like about an inch of gravel at the bottom, but I know that for a 20g tank I should have ~20lbs. of gravel, is this correct or should just go for what I like?

[*]Plants

• Totally clueless on what to do here.  
• I want to get good plants but I'm stuck on what to add.
• I currently have 3 japanese moss balls (When I moved my larger one during a water change I noticed it was partially split in half so I just popped the two halves off (one slightly larger than the other) and re-rolled them (internet helped on this).  Both subsequent balls are very green and fluffy and my shrimp loved them.
• I can get amazon swords and some other things from my LFS but I noticed they have snails*

[*]Fish?

• In this tank will be (possibly)
  1 Half-moon (possibly) double tail Betta (male)
• 4 Neon Tetras
• 1 bumble bee goby
• 3 glass catfish (from my previous thread I learned they need space)
• some ghost shrimp, and two of the shrimp that are just larger than them (mistaken for bamboo which are way too big to be my guys)​

 
*  The snails are not the mystery/apple/good larger kind but the smaller annoyances.  They are in their tanks so I'm hesitant about getting them as I know they can be transferred with the plants.  I know from experience that betta's can eat them and I can get an assassin snail easily enough but I'd rather avoid infecting my tank.  I believe I can place the plants in tap water with salt for a few hours to kill them off but I'm not sure what to do.
 
Any advice on what I will need in addition or should change would be greatly appreciated.
 
Also, I am tempted to do a full transplant of both tanks and setup my 5g over again as this would give me ~8g of pre cultured water, but to have to recycle my 5g seems a waste.  Alternatively I might run my 5-10g filter from my second tank which is being replaced by this larger one alongside the 20+g filter (I like to have larger filters makes me feel better) to help speed up the cycling but I'm not sure if this is a viable solution.
 
Currently my fish are doing well (healthy) in the tanks I have, but I've lost a bit of faith in my LFS (petco is the one that I usually go to) after they sold me a bumble bee goby and said it could be fed flakes.  After research I realize that I've been underfeeding it (though it does eat some flakes I still don't feel right) and am disappointed.  Yes I know that they wanted to get the sale but I've developed a relationship with most of the staff and they haven't really given me bad advice except for him (and possibly my glass catfish).
 
Thanks for any advice on what to get and the best way to go about doing this.
 
Thanks in advanced,
 
AJNOZ

 

[attibones]

First thing I would like to note: You need to rehome those glass cats as soon as possible. They should not be in any tank less than 90x30cm (36x30inches) according to Seriouslyfish, but I feel that this would be a very tight stocking as these fish get rather large and need the space for a large school as they are very shy fish. Either way, they don't belong in a twenty gallon. You could increase your tetras after this, but I wouldn't add in the betta because the tetras may be too nippy for the betta, or just too active. I would also not put the goby in a community tank. It seems that they do not do well in communities and also seem to benefit from water much harder than what the neon tetras can handle. 
 
Right then.
 
I would shoot for a filter with at least 200 gph turnover. You may want to have two filters on the tank to accomplish this (I've got two oversized filters on my 20 gallon and two filters on my ten). This just makes sure that you're getting enough water movement. It helps if you can cycle each filter in separate tanks because there's no way to be sure that nitrifying bacteria will just evenly distribute themselves in both filters.
 
Lights: this is really up to you and depends mostly on the species of plants you'd like. You can probably get a decent deal on some T8 or T5 hoods. You can go LED if you'd like, but these are generally more expensive.
 
Plants: I've been told that amazon swords aren't a good fit for these smaller types of aquariums because they get so large, but I've had success with mine. Other good low-worry plants include any of the anubius species, java ferns, mosses, many crypt species, amazon compacta, bacopa, water wisteria, duckweed, hornwort (which I hate), and stuff of that nature. Most of my tanks are stocked with these plants. If you don't want any snails in your tanks (and by the way, these "little annoyances" are most likely very small pond snails or apple snails), just give your plants a bleach dip for a few moments, or take the time to rinse your plants in  some separate water and pick off the snails. Most of these will do fine in gravel substrate (about an inch or so for the smaller species of plants should do it, but it's really up to you), but some of them like the java fern will need to have their rhizomes above the substrate. I like to tuck the roots of these sorts of plants into holes in my Malaysian driftwood, but a bit of fishing line will secure the rhizone to stones or wood pieces as necessary.
 
A note on "precultured water": There is very little beneficial bacteria in the water of our aquaria. Most of that bacteria lives in the filter. So draining the water of your tanks to add to the new one would do nothing for cycling filters. If you wanted, you could add the media from your small tanks into the larger, but it wouldn't be enough to support all your fish.

 

[AJNOZ]

Thanks for the information,
 
I have to ask about the catfish though b/c 90x30cm is 36x11.8 inches, not 30.  Also since they never give a hight I'm assuming that it would be ~12 inches which would give me a tank with dimensions: 3ft x 1ft x 2ft which is 22.41g so a 20g tank would be alright (though a taller tank would probably be better).
 
As for the Betta with tetras, I've never had too much issues with them picking on the Betta, mostly the Betta chases them around but their usually too fast for the betta.  After a while the Betta tires and just huffs at them and the Neons learn to stay away.
 
As for the plants and the snails, I have one snail already but I'm glad to know a bleach dip won't hurt the plants.
 
Along the lines of pre cultured water, I more meant that I'd be transferring everything from the cycled tank (filter, gravel, water) to the new tank, not just the water.  I do know that I'd probably end up having another mini cycle as the bacteria replicate to handle the increased bio load and larger water column.

 

[attibones]

Right, but you don't have to add the water at all. It's just like doing a large water change. I'm assuming that your tap PH match the tank pH.

Also, I do see my typing error with the dimensions. You'll have to forgive me. Regardless, glass catfish aren't suitable for a twenty gallon. Height is not much of a factor here because fish swim side to side and not up and down. Footprint matters more here than actual height. Longer tanks are always better for these sort. They are slow moving and can reach sizes of around five inches. They need larger than the average "six to a school" rule because they are so naturally shy. They just don't work well in this set up.

As far as the betta goes, just be sure to have a spare tank on hand. You never know when something can go wrong.