Long before I went away to college, I had 10G guppy tank. Had a lot of fun but now that I have my own place I'm looking to do a 20 or 30 gallons tank.
Looking to do a long tank, longs are better than talls right ?

Location will be in the basement, have a small window and it gets decent light during the day. I can put the lights on a timer, but dont remember how many hours of light they need ?

Filtering, this is probably the most important thing... long ago, I used one of those whisper and often find that the fry gets suck up and swam in the filtering camber ! luckily they were still alive.

For a 20/30g tank, should I even use power filter ? I'll probably start with 1 male and 2 female or 2 & 4. Plant enough fake plants and some decoration for frys to hide. I dont know if I'll be separating the frys or do survival of the fittest and leave them in there.

In the old days, I end up putting one of those circle sponge filters on the inlet of the power filter to prevent the frys from being sucked up.. not sure if it really worked or not..

I like those eheim nano corner filters but its probably not enough for a tank this size.

Longer tanks let more oxygen get dissolved in the water and give fish more room to swim back and forth.

If you added some live plants like duckweed and java moss you wouldn't really need a filter and it would also give the fry a place to hide. I sometimes get a weird white film over the top of tanks with no water movement but it doesn't seem to happen when I have lights on the tank.

The amount of light would depend on if/what live plants you have and how fast the algae is growing. If the lights are just so you can see the fish, you would only need them on while your watching your fish. You could put it on a timer so that the lights are on during the times you're normally in the room.

I never used real plants before.. I think i'm going to try it.


If I buy say java moss from LFS, do I have to do anything special, ie wash it before dropping it into the tank ?

If you're worried about snails you could wash it but you don't really need to. Duckweed floats and java moss doesn't get nutrients from the substrate so you can grow those even in a bare bottom tank. If you want to grow plants that root into the substrate you should get something other than gravel. Java ferns also grow fine with just gravel.

I would suggest going with a filter. My guppy tank has over 60 fish in it and without a filter I'd be doing water changes everyday. I have water sprite (water wisteria) in the tank too, I'd recommend getting that, its very hardy and grows very easily. Also Cabomba, another very easy plant, and it grows very quickly. My light is on about 8-10 hours a day and I've seen very little algae growth.

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50 Bowfront, 2 Acei, 2 Yellow Labs, 1 Orange, 1 Albino, 2 Blue African Cichlids
30 Gal, 3 Fantail Goldfish, 1 Black Ryukin, 1 Common Pleco
20 Gal, Mollies, Platies, Cories, Algae Eaters
15 Gal, Swordtails, Balloon Mollies, Rasboras
10 Gal, 2 Knight Gobies
10 Gal, 2 Bolivian Rams
1.5 Gal, Male Betta

Guppies should have about ten hours of light. As for filtration you do need it.i find sponge filters only have the advantage of not sucking in fish but they are very loud and dont do the job quite as well.i recommend placing live plants because they helpp filtration. Also you could get javva moss or another thick plant fake or alive for the babies to hide in and place it away from the intake of your filter. That way they would generally stay away from the high water flow

For a guppy mass breeding setup I would just recommend getting some duckweed to float, as it sucks up nutrients and keeps that nitrogen at bay pretty well, some java moss, pretty much care free plant, and a couple sponge filters. I don't really know about a 'loud' sponge filter, any louder than an airstone anyway. You can get them pretty cheap shipped straight from hong kong on eBay, buy 6 and save on shipping! I usually don't like the sponges they come with, I just buy some new ones that don't clog as easy from my lfs. Give em a couple good squeezes in some de-chlorinated water every couple weeks. I just use the water I take out in the water change. Some snails in there aren't gonna hurt the guppies and they will help keep the place clean. Bare bottom is easier to clean. If you are going for plants, all they really need is 8hours. I promise. Less prolly won't hurt, especially the java moss. That is pretty much my recipe for a 'guppy mill', haha.

I have a 29g guppy/balloon Molly setup. I have the wisteria in my tank. I left a little clipping of one float to the top for the fry. The best thing about wisteria, you don't need anything special for it, and you can take clippings and pant those and get a new plant there. The fry can really hide out in there and it helps when the females give birth, they can really hide in it.

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Tank: 29g:guppies, balloon mollies, swordtail, 2 mollies
Hex: opaline gourami
10g 1F. betta