PLANNING AND DESIGN
Consider the following questions and design your tank around them. I’ve prioritized the question in order of importance:
What is your budget?
If you don’t have a lot of money, don’t spend a lot of money. Keep the design real low maintenance and low energy. This would be buying a small-medium size tank. Do not buy a large tank as you’ll go through more product like water conditioner, fish food fertilizers, etc. Find plants and fish that will work well with your tap water. Buy a low PAR light that will work well with slow-growing plants like Anubias, Java ferns, crypts. Just don’t buy too many plants as you might get into a situation where you’ll need Co2 to fend off hair algae. Reuse a piece of furniture as a tank stand. In my opinion, the only equipment I would NOT cut corners on, is your filter. Again, I would get something a little bigger than you need just to make sure the good bacteria is protecting your fish from ammonia and nitrites. If you have some money to spend on a nice setup, go for it! There are a lot of higher-end tools and equipment that will make your life and the hobby a lot easier. And as I’ve said before, the cheap comes out more expensive. Invest in some good equipment upfront to avoid issues later. When figuring out your budget, look at your purchases in this order as they dictate how much your tank will cost:
Tank and stand – Size of the tank, type of glass. Remember a larger tank requires more of everything else you need
Filter – The size of the tank dictates the size of the filter you will need. Larger canister filters for bigger tanks obviously cost more than a smaller hang on back (HOB) filter for smaller tanks. The general rule of thumb is get a filter that will turn your water volume over 10x.
Light – PAR output (lower PAR is generally less expensive) or features generally dictates the price
Plants – The amount of PAR your light can output will dictate the plants you can grow. You generally don’t want to put a bunch of fast-growing plants under a low PAR light as they won’t grow. On the flip side, you don’t want to put a bunch of slow-growing plants under a high PAR light as they will grow algae. As a reminder, 0-40 PAR is a low powered light, 40-80 is medium powered, and 80-120+ is considered a high powered light
Substrate – An inert substrate like sand and gravel is going to be cheaper than an aquasoil, but almost all plants do better in an active substrate, like an aquasoil. When choosing your plants, make sure you are double-checking what water parameters they need, PAR, and nutrient. Most rooted plants like Alternanthera Reineckii will benefit from or need an aquasoil to thrive.
Hardscape – One does not "need" hardscape to have a successful tank. It is more of an aesthetic thing. You can skip this if need be. You can source rock and wood locally, but you run the risk of introducing parasites and algae into your tank. See information on bleach dips.
Support equipment and products – These are smaller things like heaters, filtration products, fish foods, fertilizers, water conditioners, etc. These are last on the list as they are the least expensive part of the setup.
What is your tap water like?
What is your GH, KH and PH. That has a lot to do with the plants and livestock you keep. If you want livestock or plants that require water with a lower GH and KH, but can’t afford to run RODI, I would suggest designing a tank that works well with the GH and KH associated with your tap water. There is a good chance that you might ened up just wasting money on dying plants and livestock.
Depending on where your GH and KH are, you can sometimes just dilute your tap water with RO water, versus having to remineralize 100% RO water. If you have a GH of 8, and you want a GH of 4, just use half dechlorinated tap water, and half RO water. That means less wastewater in the end.
It is more sustainable for those on a budget to use your tap water as making RODI water is more money and time. When using tap water, water changes can be as easy as draining the tank, tossing a hose back in and filling her up. The easier you make the tank on yourself, the more consistent you’ll be which tanks thrive on. Now that isn’t to say that RODI water is bad, it's actually the opposite, it gives us more control over water paraments in our tanks as we have little control over what is coming through our tap water. But with that control comes time and money. It can take hours or days to make enough water to do a tank change with RODI water. Then there is the added expense of the RODI unit, the replacement cartridges, the water (or its waste), the bucket and/or auto turnoff system. I use RO water in my smaller tanks as I don’t need as much for a water change. And then I design a system that uses tap water for my larger tanks so I don’t have to worry about making RO water and remineralizing it. Remember, when your tank gets bigger, so do the costs associated with it.
How much time do you have?
Now let’s say you have some extra money to put into a tank, a good light, some Co2, and plan to use your tap water, just be conscious of your time. If you don’t want to spend more than 30-40 minutes a week, again, maybe design a tank with slower growing plants that do not require a lot of trimming. Stemmed plants with good lighting and Co2 need to be trimmed and replaced often. This can add an additional 30-40 minutes on top of a normal 30-40 minutes for your water change. Running Co2 can also require you to refill or exchange your tanks creating an extra step in maintenance. Once can still have a beautiful Co2 injected tank that is low maintenance if you choose the right plants.
Will it fit?
How large of a tank can you fit? Will you need to block light coming in from outside? Will your floor support the weight of a large tank? This is less of a priority as a lot of us already have an idea of where the tank is going to go. Just make sure your floor can support the weight for those larger tanks. And also ensure that it's not going to be receiving any direct sunlight from any windows. Also as a reminder, make sure there are not going to be any little humans or animals that will be climbing on this furniture. If there will be, as a reminder, make sure to anchor your tank’s stand.
What kind of design do you want?
Once you figure out how much money you want to spend, how much time you want to put into your tank, and then the location of the tank, you can then think about a design that will fit into those restraints. I see a lot of people say, I want a massive 250-gallon discus fish tank (low GH and KH fish) without knowing anything about what they need. They have hard tap water, no money for an RO unit as the fish need a softer water, not a lot of time for large water changes and then they fail. Set realistic time and money budgets for yourself. The more consistent you are the more the tank will thrive. And if you have all the time and money in the world, just make sure you do your research on what kind of water parameters your plants and livestock need, and make sure they complement each other. For example, its not ideal to put hard water plants with soft water fish. OR, don’t heavily play a tank with fish that are doing to uproot or destroy your plants like some cichlids do.
Image from DiscusGuy.com
Just know as a general rule of thumb, larger tanks take more time and money to maintain but are a little more stable because of the large body of water. A drop of bleach in a 250-gallon tank will be FAR less detrimental than a drop of bleach in a 10-gallon tank. Now, this is an extreme example as we are not tossing bleach in our tanks, but there could be a time where you’re processing a water change and there is something funky in your tap water than you’re ignorant to. It will have less of an impact on a larger thank than a smaller one. I would suggest getting something like a 30-40 gallon tank as this is a great starter tank. It's not too small as to have large water parameter swings, but it's also not too big as to break the bank with water changes, buying a ton of plants in the beginning, and even supplements. You’ll ultimately have less trouble finding balance in your tank if you plan well and get the right set up from the start.