What plants would work in a 20gallon long tank?

Hello. I was planning on moving my glowlight danios (danio choprai) into a 20 gallon long tank. I was wondering what plants would work the best in this size tank. Its not a very tall tank, so should I avoid stem plants? Any suggestions? Also is a HOB filter rated for 60 gallons going to be a problem for a tank this size? Will it create too much surface agitation for a CO2 system?

What plants would work in a 20gallon long tank?
Any CO2 you inject into the water will almost immediately be released into the air by your HOB. The surface agitation it creates will allow the CO2 to dissolve into the air, making your injection entirely worthless. You could either raise the water level high enough that there is almost no surface agitation (though this could be bad-- Danios are good jumpers), replace your HOB with an internal filter, or just not mess around with CO2 at all and grow easier plants.





Assuming you have the standard, 15 watt bulb, plants like Water Sprite, Hornwort, Crypts, Swords, Vallisneria, Saggitaria, Pennywort, Bacopa species, Lilies (Nymphaea species), Banana Plant (Nymphoides aquatica), Hygrophila (corymbosa 'Compacta', polysperma, or difformis), Anubias, Java Moss, and Java Fern. While some may grow tall, that is not at all a bad thing. It gives a tank depth, as well as something for the Danios to take cover in if they are startled.
Reply:Try some moneywort or hornwart. and that filter should be fine for your CO2 system
Reply:Yes, the filter is too much for that tank. I'm only running a HOB 40-gallon for my 30-gallon tall tank. There is almost no surface agitation.





I'd use one rated for 30-gallons and place it in the center of the tank. You could also use to smaller filters, one on each side.





I would avoid swords. What you can have in the tank really depends on what kind of lighting you have.





Here are some plants that I like... sorted by lighting...


Low (under a watt per gallon): anubias, java fern, crypts


Medium (1-2 watts per gallon): java fern, some crypts, hygro (if you can find it), apongeton (grows VERY fast), dwarf lily, foxtail, myriophyllum, anubias frazeri, bacopa


High (2.5+ watts per gallon): rotala indica, rotala wallachi, pomageton gayi, red foxtail, red tiger lotus, bacopa





There are TONS of options, and it really depends. Check out the link below. There are profiles of lots of different plants and their requirements. Your options are endless.
Reply:many different types of sword plants do not get that tall. there are tons of plants that stay short and still look nice
Reply:If you want a no-fuss, easy to care for plant, I'd recommend java ferns. They can grow in low light, lotsa light, little light, and are quite forgiving of temperature, pH, etc. fluctuations.





I bought a small bunch for $5 for my 30g tank...and now it's multiplied like crazy and taken over the entire tank. I have to constantly rip some out (they spread like strawberries via rhyzomes or produce miniature replications of themselves at the tip of their leaves), but better to have them multiplying than dying on ya! A lil bush in the corner should suffice.





You can trim their leaf density quite easily by snipping them at the stem. The danios will enjoy their coverage and probably rest under the leaves. Sometimes the leaves yellow and die, but then they float to the surface, and I can remove them quite easily. My only complaint are the baby plants that do unattach themselves from the mother plant and start floating around - can get sucked up into your filter.





And yes, that filter is too 'big'. Too much 'filter' creates too much surface agitation and cycle way too fast.