it is not imperative that you have a filter. If you change 50% of the water every day/every other day and dont overfeed the fish they will be fine. Getting a liquid test kit is important as well so you can test the water and get an idea of how often/how much to change. Filters make it easier for US because they cut down on waterchanges. So if you are planning on upgrading their tanks they should be fine in the mean time. Anywhere from 3gal with the male(5 is "better" for beginners until you get the hang of water chemisty..larger volumes of water dilute the waste more) and 10 would be great for the females as them you could get some more
they DO need heaters (or at least keeping thier water between 72-78 degrees F). If you cant find very small heaters at walmart (25 watt heaters by tetra) for around $9. They also enjoy plants or other cover in their tanks. Live plants would be best (like anacharis/elodea, wisteria or camboba. They will help somewhat with the ammonia and nitrites in the tank as well. again, can generally find these plants at places like petsmart/petco. Cheap and easy to care for (dont really require much care at all to be honest...good for beginners). a syphone and bucket will make waterchanges easier for you. Id recommend you get some...and some dechlor (pond dechlor is super concentrated and is fairly cheap. one big bottle will last you MONTHS even changing water everday on each tank. You only need a tiny amount.
you could always MAKE your own small filter:
ive just copied/pasted from an old PM. ignore any info that does not pertain to you/your tank. the build will be the same tho.
ANY questions/clarifications feel free to ask-im a HUGE advocate for these filters for so many reasons.
here's how to make one. it is reallllly simple.
list of things you will need:
- an old fish food tub or any other plastic container with a lid depending on the size of the tank to house it (like an old peanut butter jar (plastic of course), big yogurt container, sour cream container, even an old well rinsed out pill/prescription bottle etc.,).
-something to poke holes in the plastic- a nail and hammer or a drill with a small. sized bit
-gravel or some other material to weight it down
-filter media (sponges work best)
-air pump
-airline tubing
now to build it:
-take the clean container and poke some holes in the bottom. like 8 or so.
-poke a hole in the lid of the container that will accommodate the airtube and be just a BIT wider than the tubing(so the air can get out as it bubbles)
-take an amount of gravel and put it in the bottom (a small handful will be enough)
-put the airline tubing thru the hole in the lid and then run it in the container right down into the gravel
-pack the filter material nice and tight around the airline tubing. you can cut sponges to fit. just make sure its packed well. if not, the airbubbles will have lots of "options" to escape. the idea is to get it so that there is good suction thru the filter as the bubbles rise. if there is lots of airspace in there, the bubbles take the path of least resistance and suction will not be as good thru the media as it should be, and the filter will not work as well.
- put the lid on the container that now is weighted with gravel and packed with media.
-turn on the airpump and viola- nearly instant and cheap filter!!!
some troubleshooting advice:
-if it seems to float, add more gravel to weight it down
-test your water daily and do appropriate waterchanges until it cycles.
-if using mature media, ive found that they usually cycle within a week or so (or sometimes instantly if the bio load is low).
- if you dont notice reduction of ammonia within a week or two, try packing with more media...or if it was REALLY jam packed, maybe take a bit out.
these filters require VERY little maintenance. they are NOT mechanical filters (do not remove the solid waste in the tank) so they dont get all gunked up with waste. i have not touched my filter media in months!!!! although this means that with water changes, you will have to siphon out the solid waste- these filters do not do that for you. they just take care of the chemical filtration (turning ammonia into nitrites into nitrates). they do circulate water quite well tho.
good luck and feel FREE to ask if you need any further instruction or clarification. they Trula are very very simple to make. once you make one, you might not buy a filter ever again. i know i wont smile.gif its a little extra work to clean the solid waste up, but if you regularly do partial water changes anyway, it is not a big deal as you should be siphoning up the poo anyway.
Thats what I got for you as a beginner. Enjoy the fish! And welcome to the forum
cheers
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