First 125 gallon tank

[Evestri]

First things first, hi to all the new people who I will be meeting on these forums! Its always a pleasure to meet new people whether online or in person. Maybe not always online.

A little bit of backstory: For a long time a family member of ours had expressed an interest in owning a fish tank for aesthetic and pleasure purposes, and recently he decided that he wanted to go ahead with building one. My cousin and I decided that we would help him build and maintain it, because we felt that due to his lack of time the fish wouldn't receive the adequate care and maintenance if he undertook the task alone. We know he is determined to finance the maintenance costs, but we would prefer they be lower than higher .

None of us have any serious experience with fish keeping. I own a Lizard, and my cousin owns a few dogs. The last time any of us have had fish was ~5 years ago and we never had any success because we were ignorant then. We both understand that the project is a commitment, and we are determined to build as suitable habitat for the appropriate fish along with their care and maintenance. We have both been busy researching cycling tanks (nitrogen cycle), a little bit of aquascaping, possible stocking options, general aquarium care etc. Although we tried to convince our family member to start smaller, he was adamant on a 125 gallon fish tank to put in his living room. We managed to convince him to do a freshwater tank instead of a saltwater tank, at least.

Since its our first fish tank, we would like to have some suggestions on possible freshwater biotopes, possible stocking options. He said he prefers "big fish" but we are also open to smaller schooling fish as well. We took some measurements of our tapwater using api test strips, and we got these readings:

PH: 7.5

GH: 7.2 dH

KH: 6.7 dH

We haven't got the tank yet, so we are hoping for some feedback from members with more experience.

 

[Byron]

Welcome to TFF. And thanks for posting the source water parameters, this is what most of us usually have to first ask for, so we can move ahead here.

Re the parameters, you want to stay with basically soft water species. GH is the more important of the three parameters, and we can generally divide fish species into those preferring (which means, will be healthier in) soft water, moderately hard or harder water, and some sort of in the middle. The harder water fish like all livebearers, rift lake cichlids, will be unhappy in water this soft so don't consider them. But that leaves us with the vast majority of fish.

Next question to answer is whether you want a tank of largish fish (the "big fish"), or a tank of smaller fish that will generally be shoaling. There are some moderately-sized fish that will suit the latter so it is not meant to suggest a tank of miniature fish. Shoaling refers to a species that lives in (usually large) groups and must be maintained in groups which can vary in number depending, but in most cases more rather than fewer is always going to mean happier and thus healthier fish.

The aquascape will need to provide what the fish you select require, and this can vary with species. You could for example do a Central American or SE Asian river/stream with pea gravel or sand (fish selection might determine sand over gravel), chunks of wood, some smooth river rock, lower plants (meaning plants rooted in the gravel substrate) or not with just floating plants. Or a South American or SE Asian stream, lagoon, or flooded forest aquascape; substrate-rooted plants, or none but lots of wood and branches with floating plants.

The lighting will be important, especially for plants (if any) but also fish. The filter is important not just for filtering but as this is the source of water flow the requirements of each fish species for current (or none) must be considered.

 

[Evestri]

Yeah, larger is better because that’s what our family member wanted with a saltwater tank before we convinced him not to. We were looking at clown loaches and thought it would be great to have 4-5 of them and see them grow. We had an idea to carpet the bottom of the tank with Java moss, with some sunken pieces of wood and rocks in the mid and foreground. Problem is I’m not sure if clown loaches would do well in a habitat like that. Other species like cories were considered as well a group of like 10 of them would look nice. Are cories and clown loaches compatible?

 

[Byron]

Yeah, larger is better because that’s what our family member wanted with a saltwater tank before we convinced him not to. We were looking at clown loaches and thought it would be great to have 4-5 of them and see them grow. We had an idea to carpet the bottom of the tank with Java moss, with some sunken pieces of wood and rocks in the mid and foreground. Problem is I’m not sure if clown loaches would do well in a habitat like that. Other species like cories were considered as well a group of like 10 of them would look nice. Are cories and clown loaches compatible?

You intend a 125g, but for clown loaches it is the length and width (i.e., the footprint) that is more important, and this species needs an 8-foot tank at maturity. They attain 8-12 inches, and they are active, hence the space requirement. There are other loach species that are not so large. Many of those in the genus Botia attain in the 4 to 6 inch range, some are quite peaceful (for loaches), others much less so.

Loaches and cories are not advisable together. Cories can frequently not feed well with loaches around because the loaches are aggressive feeders--and by aggressive here I mean they are much more determined to get the food and other fish take a back seat or may be attacked. On his Corydoras World site, Ian Fuller has said not to combine loaches and cories, and Ian knows more about cories than most all of us put together.

If you decide on cories, you need sand. Play Sand is safe, and very inexpensive especially when one is doing a larger tank. Avoid white at all costs. I use the dark grey play sand, and I believe there is also a buff one. A larger group, 30-50 if this is a 4 or 5 foot tank. You can mix species, but try to have several of each species when you can get them. I have 50 in my 70g 4-foot tank representing 11 species; some species were acquired as one or two or three because that is all the store had. They chum around together no matter, and the more the happier.

 

[Evestri]

That is very useful information, thanks! We were definitively hoping for cories, as they were very appealing. However they probably wont be a great fit. We decided that we want a heavily planted bottom, so we are likely to get some plant substrate and have a carpet like java grow on the bottom. Do you know if any bottom feeders would be appropriate in a heavily planted bottom?

 

[Byron]

That is very useful information, thanks! We were definitively hoping for cories, as they were very appealing. However they probably wont be a great fit. We decided that we want a heavily planted bottom, so we are likely to get some plant substrate and have a carpet like java grow on the bottom. Do you know if any bottom feeders would be appropriate in a heavily planted bottom?

OK, this brings up some issues now. First, plant substrates are frankly a waste of money. Here I should mention that there are various types of "planted" tank. A high-tech planted tank is one with mega lighting, diffused CO2, and daily nutrient supplements. It is basically an aquatic garden and the plants are the focus, sometimes with no fish at all. At the other end is the low-tech or "natural" planted tank, where fish are the focus of the tank and the plants are just there as secondary or part of the natural aquascape. And obviously there are various in-between methods. The plant substrates might be beneficial in high-tech, but not in less. And fish if present need to be your prime concern, and some of these substrates have issues for fish.

Plants on the substrate can be problems in themselves; obviously they need good lighting, and fish are affected by light so this is another issue to work out. You mention java...I am familiar with Java Fern and Java Moss, and both of these are low to moderate light requiring, but they attach to solid objects like wood or rock.

 

[Evestri]

After some discussions, our family member changed his mind. We won’t be going ahead with the 125. Thanks, sincerely for the help.

After all our research, fish keeping seems interesting. I’ll definetly be using your feedback to setup my own project.