Prepping for a first time aquarium ("The Plan")

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My kids have been asking for a pet for awhile now, so I started looking into something that's fun but manageable. Dogs are great, but it's like having a toddler that sheds fur for 15 years. We need something that fits the busy stage of life we're in right now. In other words, fish!

What follows is in no way the opinion of an expert - or even an amateur! In fact, it's just a brain dump of everything I've been reading over the last couple of weeks, trying to figure out how to get an aquarium started with minimal mistakes. I've been reading and posting on forums, comparing reviews on Amazon and pet store sites, and in general burning myself out before even starting. Take everything that follows with a grain of salt.

Here's my (two-part) plan... we'll see it how it goes...

Part I - The Water

Although some people seem to do just fine with treating their water, waiting a few days, and tossing fish in, it's apparently preferable to prepare the water first - a process that could take weeks.

Nitrogen Cycle

Start researching how to care for an aquarium, and sooner or later you'll stumble on the nitrogen cycle. I've never heard anyone with a fish tank talk about it, but if their first fish got sick or died this was probably why. This diagram sorta shows the flow, although the article it came from was over my head. :)

Image credit: Biogeochemical cycles: Figure 4 by OpenStax College, Biology, CC BY 4.0. Modification of work by John M. Evans and Howard Perlman, USGS

Basically, the "nitrogenous waste" in an aquarium setting is fish poo and decaying food (since those flakes contain fish, shrimp, vegetables, etc), which produces ammonia... and eventually, sick or dead fish. But if you take the time to let the right kind of bacteria build up, it'll convert the ammonia (NH4) to nitrites (NO2) for you. (Yay!) Unfortunately, nitrites are also bad for fish. (Boo!) So you take more time and let some other kind of bacteria grow that turns nitrites (NO2) into nitrates (NO3), which are less harmful. (Yay!) But not harmless. (It's just a rollercoaster of emotions here.) You'll still need something to clean it up, including live plants, filters, and/or (most importantly) water changes.

Encouraging Bacteria

The bacteria need something to grow on, so I'm getting a couple sponge water filters (they're really inexpensive - here's another that's more suitable for smaller/shorter tanks) connected to a Tetra air pump to encourage that growth. Gravel (substrate) can really help too, from what I'm reading, and I was fortunate enough to pick up about six 5-pound bags of aquarium gravel at a garage sale for 50¢ apiece. In fact, if you're patient then garage sales are a great way to go... I got a 20 gallon tank, cover, and light fixture for $20 too, which is probably at least ⅓ what all that would've cost from the store.

They also need heat... or it helps at least. Unfortunately, every heater - no matter the price, brand, or number of ratings - has reviews (sometimes hundreds) with photos showing the aftermath of these things overheating, cracking, or shorting out. I guess part of keeping an aquarium, of creating this whole mini-ecosystem in your living room, is accepting that something bad may happen. I'm going with an Eheim 75 watt. They seem to be (or were) a good brand, and their stuff seems to be made in Germany. There are sites with charts for which size heater matches your tank size, and for my 20 gallon in a relatively warm house, a 75 watt should do. Plus maybe if it overheats it won't cook my fish as quickly. (How's that for optimism?)

Since the built-in thermostats are frequently 5 or 10 degrees off (according to the reviews), I bought a thermometer too. Lots of reviews of suction cup ones breaking - either after coming off the side or just when people were adjusting them. Luckily, they use alcohol now, but it's still a mess. I purchased a floating thermometer - I'll just have to figure out a way to secure it so it's facing the front.

One last thing - if you have city water, they add chlorine to ensure it's bacteria free (a good thing); unfortunately it also kills the bacteria in your aquarium and makes your fish sick (a bad thing). You'll want a product like Seachem Prime that neutralizes it. I have a well, so I'm not concerned, but I'll get it later because of its other benefits. It also claims to neutralize ammonia, so I'm not sure how that affects someone trying to do fishless cycling (where you want ammonia)... I suppose you'll just have to use a little more ammonia than Prime can handle.

Fuel for Bacteria

But the bacteria won't grow without some fuel first. I read quite a few suggestions on how to provide that fuel, but these seem to be the most popular:

  • Get a fish, knowing it'll be stewing in its own "nitrogenous waste" until the bacteria develop. Hopefully it doesn't die.
  • Toss in some food each day, waiting for it to start decaying to produce ammonia. Clean up a disgusting, flaky, moldy mess afterwards.
  • Use 100% pure (clear, unscented, no additives) household ammonia from the store. Handle with care!

I decided to go the ammonia route first, but it proved a little difficult to track down. Then I stumbled on a post that suggested ACE Hardware had the right stuff, and I have one right around the corner. The 32oz container is $2.60 which is way more than enough. A couple people were even kind enough to leave reviews... who knew ACE would be the goto place for aquarium enthusiasts doing fishless cycling?

In trying to figure how much to use, one site recommended increasing the water temperature to 80°F (27°C), adding five drops of ammonia per ten gallons daily until nitrites show up, then backing off to three drops daily until everything levels off. It's good to compare a few sources though. Another article (20 years old, but if it worked before why would it change now?) suggested pretty much the same - crank up the heat to mid-80s and add 3-5 drops a day or as much as it takes to register a lot of ammonia with whatever tester you're using, then wait for it to decrease. It's a place to start at least. Also, the kids won't be helping with putting this stuff in the tank - it's nasty and full of dire warnings.

Seachem Stability is supposed to speed up the process with a special blend of hardy bacteria to kick off the nitrogen cycle; but since this bacteria is apparently around us all the time anyway, I'm gonna have a go without it first.

Tracking the Cycle

While the cycle's cycling and the bacteria are doin' like they do, you need to test the ammonia and nitrite levels (and eventually nitrates too). I'm getting a Salifert ammonia test kit and nitrite test kit, to make sure the cycle is complete before getting fish. I also want to test the water when adding new fish or changing filters, both of which can lead to increased ammonia and nitrite levels. Salifert sells a nitrate test kit too, and when the cycle progresses along I'll get it so I know how often to change the water. There's no way to get rid of the nitrates completely anyway, so I'll avoid overstocking and overfeeding, and get into a weekly water change habit. API has a convenient all-in-one freshwater test kit that would be cheaper than all the Salifert ones combined, but there are too many reviews (with photos) about kits arriving with chemicals leaking inside the package and during usage.

Water softener salt

We have a well, so we also have a water softener. It works by effectively removing other minerals from the water, but the process does add a small amount of salt to the water. Is it too much? Answers on several forums ranged everywhere from "I have not lost any fish yet in this water" to "I would not use water softened by salt in any of my freshwater aquariums". Internet fail. I'll start with softened water and if the bacteria thrive, I'll assume the fish can too. If I see no nitrites after awhile, I'll figure the bacteria can't survive it and switch to unsoftened water. Our softener has a bypass but it's less convenient than just turning on the faucet.

pH Levels

Yay, another metric to worry about! Your water's acidity (low pH) or alkalinity (high pH) plays into which fish you should get and how well they'll do. It sounds like most city tap water is neutral (or should be) but I'm sure it varies. Being on well water, I had no clue how far off neutral ours might be, so I went to a Pets Supplies Plus store where they'll test water for free. I brought two samples with me - the strip on the left is without salt (and the hardness level indicated very hard, or red), and the strip on the right is with salt (and the hardness is very soft, or green). The pH level (bottom color) is pink, so our pH is apparently at least 8.4... maybe higher.

I bought an API pH test kit (there's also tests for testing a wider range of pH levels) since they're pretty cheap, and I'm curious if it'll match the store results. I may periodically bring samples to PSP again to have them re-test. I really don't want to add drops to bring the pH down, because I've read that it can cause pH to swing wildly which is awful for fish, and it must be applied often. On top of that, the drops are usually sulphuric acid, so.. yeah, not friendly stuff. Instead, I'll stock fish that do well in in high pH, like african cichlids.

In looking for natural ways to affect pH, numerous sites that mention driftwood, sphagnum moss, peat moss, and catappa leaves to lower it (or coral to raise it). Good to know if it comes to that, but I'd rather make due with what I've got instead of adjusting and testing the water forever.

Part II - The Fish

Right now, I've only purchased enough to do the cycling, but when the water's cycled it'll be time for picking out fish... and more stuff to consider! Whew...

Slime Coat

I'll get Prime because it provides slime coat for fish, which apparently is vital to their well being. There's another highly rated similar product called API Stress Guard, but even though Prime is nearly 2x more for the same amount, it goes 5x further! (5 ml per 50 gallons vs 5 ml per 10 gallons)

More filtering?

I couldn't decide whether to get another filter besides the sponge water filter. If an aquarium has a biofilter full of good bacteria, and you change the water frequently, what does (for instance) one of those little Tetra in-tank cartridge filters with carbon actually do? I've known a few people who kept fish, and we even had fish when I was a kid, and I can't recall ever seeing a really clear tank. There's usually "stuff" floating around, and they're even cloudy or green, but I think that has as much (or more) to do with water changes than one of these little filters.

According to an answer I got in a forum, and what I read on other sites like thesprucepets, the carbon present in these filters is mostly used to remove phenols (something that causes odors), tannins (from decaying organic matter like driftwood and leaves), leftover medicines (if any), and chlorine (not a problem in my case). They don't apparently help get rid of ammonia, nitrite or nitrate, which is what the sponge filter and cycling is for anyway. And to top it off, fish could get stuck in the intake vent or jump into the top of the filter. I'll see how it goes with two biofilters in the tank (one on each side), so there's plenty of area for bacterial growth and good circulation. I might get a "bubble stone" for the tank too, if the circulation still seems inadequate.

Gravel cleaning and water changes

One thing everyone seems to agree on is to get a gravel vacuum... a fancy term for a length of hose that lets you siphon dirty water from the tank and hopefully suck some crud up from the gravel at the same time. The best rated one on Amazon was this python no spill system, but it's pretty expensive, especially if you don't need the 25 foot length. Nothing else was overly exciting, and since Walmart has a few and returns would be easier, I may just use them when the time comes.


There's not a whole lot to say about this, except that I've been reading about fish that prefer bloodworms and cabbage leaves, filet mignon and half-racks of ribs, and other stuff I'd never even make for myself. I'll be looking for a few fish that are okay with some scrumptious flakes like these TetraMin Tropical Flakes, which despite the name seem to be for any fish.


Last but not least, fish gotta have something to look at right? This set looks nice for a shorter tank, but since mine is about a foot tall I'll probably go for a slightly taller set. They're both rated well. I can't imagine much going wrong, other than some cheap plastic falling apart and poisoning the fish... something minor like that. Anyway, some plants (even fake ones) give the fish places to hide, which apparently reduces stress for certain types.

This is gonna be a learning opportunity, but I hope a good one!

If we just keep it like this, it'll be a lot less work...


Grant Winney

I write when I've got something to share - a personal project, a solution to a difficult problem, or just an idea. We learn by doing and sharing. We've all got something to contribute.

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