Fish for the upper half

http://rainbowfish.angfaqld.org.au/Melano.htm

http://rainbowfish.angfaqld.org.au/Kamaka.htm

Small (2-3 inches), peaceful, not normally as blue as in the picture, males have long pointed dorsal and anal fins, females have shorter rounded dorsal and anal fins. Keep them in groups of 8 or more. Easy to breed. Feed them a variety of foods including plant based (goldfish food) and duckweed.

I had problems keeping them in Western Australia and we couldn't work out why because they were local bred. But most other people kept them without any issues. They were about the only rainbowfish I ever had issues with. I must point out that the New Guinea rainbowfishes kept in Australia originate from a very small number of eggs that were smuggled into the country, so their genetics are pretty crap. If you live outside Australia you will have better quality fish and probably no issues with them.

I'm in the US. The pic I posted definitely shows more blue than those at the LFS. They were not inexpensive at $13 each so, hearing that you had problems with them is discouraging.

All of them were 2 - 2.5 inches. While watching them from a distance, they were in constant motion. When we approached the tank, most stopped and watched us. When we put a hand near the glass, they would all move towards it. Certainly an interesting fish. If most rainbows behave like this, I don't know why I have never considered them in the past.

It is a good sign when the fish watch you and come to the front for food when you move your hand near the tank. It means the fish are happy, healthy and aware of you and what is going on around them. They sound like good fish to try, even if you only get 2 pairs (2 males & 2 females) or 1 male and 2 females.

All rainbowfish and generally all fish will quickly learn to associate people with food and come to the front whenever you go near the tank. Fish that are kept in a dark corner of the house where nobody goes will become shy and nervous and hide when you are around. But fish kept in a lounge room, kitchen or somewhere that has lots of movement and people will tame down within a few weeks.

My rainbowfish lived in the loungeroom and as soon as they saw my bedroom door open, they all swam over to the side of the aquarium closest to my room. As I walked past the tank they followed me as far as they could. They didn't do this for anyone else in the house so they can recognise and differentiate between different people.

They have very good vision, which they use for hunting insects and small aquatic organisms, and they display bright colours that also indicates they have good eyesight.

All rainbowfish jump so coverglass are required, and they need plant matter in their diet. I fed them goldfish flakes and pellets along with various frozen (but defrosted) foods, live foods, freeze dried foods and I always had Duckweed growing in the tanks. The fish ate the Duckweed and left most of the other plants alone. If they ran out of Duckweed then they would pick on the Ambulia and Hygrophila polysperma, at which point I would grab Duckweed from a pond or another tank and fill their tank back up with it.

Sounds good. If I do get those rainbows, I'd go ahead and get 8-10.

I just found a good deal on, and bought, a used 75 gallon (48 inches long X 18 inches wide X 21 inches tall) aquarium. It was still up and running with several fish in it. 2 angels, a Bala shark, a black ghost knife, a pictus cat, an emerald cory and two plecos, one pleco is 4 inches, the other is 8 inches.

My friend came and helped me break it down and move it. I gave him all the fish as thanks. He has nearly a dozen tanks up and running and has room for all the fish, and with good tank mates.

The only fish I might be interested in is the pictus cat, if it would get along with the rainbows. I would definitely buy additional pictus, probably 6 total. Though, I think I'd rather have kubotia loaches patrolling the bottom of the tank.

Pictus are generally ok with bigger rainbowfish but I would be cautious putting them in with the smaller species. Pictus have big mouths and are nocturnal predators and might have a go at the rainbows. Loaches or Corydoras would be better tank mates for the rainbows.

I was wondering if that would be the case, especially once the pictus reach 6+ inches. Kubotia loaches it is.

The tank came with 2 HOTB whisper 60S and about 2 years of replacement filters however, my friend highly recommends using a canister. I may eventually go with a canister.

I will need a heater. I'm in a basement apartment and it stays quite cool so, I'm thinking of using an oversized heater. What heater would you recommend for, lets say, a 125 gallon aquarium?

For the first time in this hobby, I plan on using no artificial decorations. I can already see black sand with 2 nice pieces of driftwood, one on each side of the tank, with anubias tied to them. In the center, a driftwood bonsai with Java moss as the greenery. I can also picture a couple stacks of stones to provide plenty of caves, with more anubias and Java moss. I also see a few Amazon swords and/or Java ferns along the back with some mid sized plants dispersed throughout the midground of the tank.

125 gallon (600 litres) tank requires 2 x 300 water heaters.

If you plan on keeping loaches, check the substrate and make sure it is smooth and not sharp, otherwise the fish could be injured swimming on it.

What sort of filter cartridges do you have?
It is preferred not to replace filter materials unless they start to fall apart. If you add sponges to the filter you can squeeze them out in a bucket of tank water every 2-4 weeks and they last forever.

You can put a round filter sponge over the intake tube of most filters and that can hold bacteria and gunk. Then you take it off every 2-4 weeks and squeeze it out in a bucket of tank water.

The only filter media that gets replaced is carbon or ammonia absorbing granules, and I don't recommend using the ammonia absorbing granules anyway.

They have a plastic frame covered with white poly-fill like media. They have a pocket that holds carbon. Over a decade ago, I used a similar style of filter and would rinse them when needed. I would only replace them when, like you said, they began to fall apart. I would only replace one filter at a time to preserve as much good bacteria as possible.

Since I have a couple air pumps now, I may also run a couple sponge filters. Once everything is well cycled, I can use these sponge filters to set up a quarantine tank for new additions.

Today, I'm going to check that the tank is level. I plan on adding the water, sand, driftwood, and plants over the next couple weeks. I'll probably use some fertilizers. However, I have a two week trip planned for the middle of next month. I will not add any fish until I'm back. I am guessing the kubotia loaches will be rather small when I purchase them so, I'll probably add them first and keep a close eye on the ammonia, nitrates and nitrites for a while.

I've never ran a planted tank before but, I read that it can almost completely negate the need to cycle the tank. I'll still keep an eye on the water parameters and only add one type of fish at a time. I definitely don't want to kill off over $150 worth of fish.

I would recommend more driftwood than just two, however large they might be. Several chunks of wood like the Malaysian Driftwood would be best; this wood is available in some stores and online, and the larger pieces often have tunnels and crevices. Loaches need hiding places, and they l;ike to select their "home" spot so providing several is better. They also spend a lot of time "playing" and chasing one another through tunnels in chunks of wood is their natural sport. I have had a group of five Botia kubotai for nine years now; originally six but lost one about a year after acquisition. The two largest do the "loach dance" all the time, and all of them are regularly chasing one another, disappearing in one chunk of wood and appearing from another.

Rock in the form of river rock of various sizes is smooth, and these fish will dig around them. Unless siliconed together if you build them up, they can collapse. And these loaches do excavate under wood and rock; mine have burrowed through the sand right down to the tank bottom glass in several places. They will arrange things as they want them. Sword plants are good, if not natural to their habitat, as their huge root systems firmly anchor the plants so they don't get dug up. The loaches do sometimes chew holes in the leaves, but not to the extent of killing them.

Floating plants are needed too, as overhead light does not sit well with these fish. Once your floating plants are growing, "cycling" is not needed. I can explain more if asked. Add the loaches together as a group, no less than five or six, so they can develop their hierarchy; later additions will not usually be welcomed. Mine have never bothered upper fish, though I would not keep these with very sedate fish like cichlids. But barbs, tetras, rasbora, danios fare OK, as should rainbowfish.

The attached photos are not the best, but they give an idea of the 90g tank I have these loaches in; lots of chunks of wood (there are four more chunks in the shadows you can't really see) and areas of river rocks with sand filling in.

Thank you for telling me about the kubotia's digging. I'll be sure to silicone the stacks of rocks together.

I would appreciate information about planted tanks and how it effects cycling.

P.S. Those are beautifully planted tanks.

Nitrogen is a macro nutrient for plants, and the majority of aquatic plants prefer ammonium [not nitrate like terrestrial plants] as their source of nitrogen. Tests have shown that plants uptake ammonia/ammonium faster than the Nitrosomonas sp. nitrifying bacteria. Obviously, the growth rate of the plants governs how much ammonia/ammonium they will assimilate, just as it does for other nutrients and light.

Floating plants are the fastest growing species; being at the surface they obviously have more light than lower plants (which is of course why all plants grow toward the light). But they also have the aerial advantage; they can assimilate CO2 from the air through their floating or aerial leaves, and this is about four times faster than for submersed plants relying on CO2 assimilation from the water. And obviously again there is no shortage of CO2 in the air, as can occur in aquaria.

It is almost impossible for there to be ammonia present in planted tanks, provided the plants are growing and the fish load is not beyond the capacity of the plants and system itself. Once you have fast growing plants, floating being the best as they will start growing immediately and be obvious about it, adding fish poses no problems. But I wouldn't go too fast with the fish just to be safe, until you have more experience with this method. The bacteria will still colonize but you will not be aware of it because ammonia and nitrite will be zero from day one. And another advantage of plants taking up ammonia/ammonium is that they do not produce nitrite. Nitrate will eventually appear, maybe; it depends upon the plant species and numbers and the fish load. Nitrate is (or should be) very low in planted tanks simply because the plants are using the majority of ammonia/ammonium so less gets through the nitrification process. Which is another bonus, since all fish are detrimentally affected by nitrate depending upon the exposure and level.

Ahh. So, my plan to have the tank fully planted for a few weeks before adding any fish would be a good idea.

You're suggesting that I could potentially add all 18+ fish at one time?

Oops you added while I was typing my reply

Yes to adding all fish, provided you have floating plants that are clearly growing. I keep stressing floating plants, but really these have been called ammonia sinks for this very reason--their uptake of ammonia/ammonium is remarkable.

You also have a large tank (125 gallons/600 liters was mentioned) and eighteen fish like loaches and rainbowfish are not going to have any ammonia issues in so vast a water volume with plants. I have re-set several tanks with new substrate and filter media (I only use sponge filters anyway, rinsed under the tap) with no issues.

My quarantine tank for new fish acquisitions is a planted 20 gallon; I have more than once had this tank empty of fish for months, then come home with 30 or 40 fish, and in they go. The surface is covered with floating plants, and I have never had ammonia or nitrite.

Colin_T mentioned duckweed. I'll risk the over growth possibilities and add some for sure. A fish net can easily scoop out any excessive growth

I plan on having the tank fully planted for at least 2 weeks before adding any fish. Would you recommend that I use fertilizers and CO2 until I add the fish?