Lessons from an Aquarium Upgrade

I made a big decision recently. I replaced my 55-gallon (208 liter) aquarium with a shiny new 125-gallon (473-liter) beast that now defines the layout of my home office. This was no small task, and I offer this series of thoughts as guidance for anyone else attempting a similar upgrade.

The Price Is Right

I considered this upgrade first and foremost because I found a price for a combined tank, stand, hood, and light set that was shockingly affordable. A kit with all the aforementioned items could easily run more than CAD$1600 together, plus taxes and delivery charges, but the price I found was a little over half that. I was not prepared to spend nearly $2000 on just the base of what would have to be a much larger project, but $900 plus tax was doable. The deal was further sweetened when a friend alerted me to a tool for accessing potentially sizable discounts on items from this pet store, which would take another $250 off the post-tax price. With this purchase taking place shortly after receiving my annual income tax refund, there was an opportunity to be a little extravagant, but that was no excuse to spend more than I had to.

The aforementioned kit did not come with a suitable filter, heaters, and other necessary items for aquarium success, so I made use of my preferred aquarium specialty store and its mail-order annex to fill the gaps in my existing inventory. Additional planted-aquarium substrate and décor for the additional floor space would also be necessary for making this project shine. My discount for being a member of the Ottawa Valley Aquarium Society (OVAS) took the edge off some of these purchases. This would still be a pricey adventure, but it did not have to sting as much as it could have.

Hypothetically, patrolling local second-hand sites, including Kijiji and local aquarist fora, might have yielded deeper discounts. However, particularly for large or heavy objects, the need to retrieve the items myself as a user of public transit and rideshares would rapidly eat into the cost savings, particularly for the tank itself, which was too large to transport in anything but a van, pickup truck, or larger vehicle, while making the whole adventure that much more logistically complicated. Paying a little extra was worth it to save that much time and effort.

Lesson: Although aquarium-keeping can be an expensive hobby, there are ways to defray those costs and they should be pursued.

Measure Twice, Cut Once

The next barrier this adventure had to cross was whether my home could handle having such a large aquarium in it. I had to measure the space it would inhabit. Some quick checks with a tape measure revealed that it absolutely would fit, with room to spare, in the space previously occupied by the 55-gallon aquarium and the adjacent cat tree. I could put the cat tree elsewhere in my home and the old aquarium and stand could go into my basement storage locker until and unless I had need of them again. With that, space was assured.

A related concern was whether my floor could handle the weight of the aquarium. A full 125-gallon aquarium weighs more than 1300 pounds (almost 600 kg), which is a considerable load and a big reason why keepers of large aquaria are usually homeowners with basements. As a dweller on a high floor of a residential tower, I could not be so certain of the capacity of the ground beneath me to support my ambitions. Mercifully, some research into the material of my floor and the loads it could bear set my mind at ease. Not only was the weight of this aquarium less than 1/100 of the most conservatively estimated strength of my floor, but the pressure exerted by the new tank was only marginally greater than that exerted by the old, its greater weight apparently almost fully countered by its greater floor area. I would have no concerns with the floor caving in under my new box of water.

Lesson: Concrete can hold up cars in parking garages; you’re fine.

A Little Help from My Friends

With all the preliminary math done, and once mail-ordered items were in hand, it was time to acquire the beast. This was something I could not do on my own. The empty tank weighted more than 200 lbs (91 kg), far beyond what I could hope to bring home on a hand-truck and more than I could realistically so much as lift safely. The store would not deliver it, so I had to enlist some helpful friends with a suitable vehicle.  They did not take as long to find as I feared they might, and I ended up with an excess of volunteers to help make this purchase happen. With three experienced lifters, one van, a second vehicle in case the van could not fit the tank and its stand at the same time, and a prearranged service elevator, getting the aquarium into its space in my home proved to be the easiest part of this entire process.

Lesson: Asking for help does not have to be as fraught as it often feels for this fiercely independent aquarist.

The Best-Laid Plans

And that’s where things started to go a little sideways.

I had big ideas about how to get the contents of my old aquarium into the new one. I spent the night before rinsing 28 kilograms of Flourite Red substrate to minimize its complement of dust. I spent the morning before the tank purchase capturing all my fish and shrimp and putting them in a heated, aerated bucket. I set up similar buckets for my Java ferns, since these plants could be moved without massive disruption to a deep root system. I brought two large scoops I could use to move the old substrate, remaining plants still in it, as non-destructively as possible, between and atop the new Fluorite completing the greater floor area of the new tank.

And then the Flourite dust hit.

Flourite is always dusty. It was dusty the first time I used it in Miami, it was dusty when I first used it with my 55-gallon aquarium when it was new, and it was dusty after adding more a few years later. The package warns of dust from the clay particles in the Flourite rubbing together in transit and smaller sizes come with porous bottoms so that they can be rinsed in the bag. The least surprising thing that could have happened was the hours spent rinsing out dust the night before turning out to not be enough, and yet, there I was, in water so dusty I could not see the bottom, trying to plant plants and add substrate without burying anything I wanted to save.  My old plants could survive only so long out of water and would lose their leaves, at a minimum, if this process took too long, but frantically removing dusty water and replacing it with fresh or trying to work in reduced water depth led nowhere. Only time would help.

With the help of one of my assistants, I gave it a few hours by heading to pet stores and procuring as many of the new fish I had in mind as were available, hoping that this time would be enough to at least enable the rest of the aquascaping. It was not. Those fish, and the fish I already had, would wait several more hours while I transferred as much as I could as painlessly as I could from the old system. It was a time-consuming, anxious, frightening, emotional, laborious, and so very dusty process. It ended only with a crying jag, acceptance that I would have to tidy the aquascape in the morning, and deciding that I needed to get my fish in there now before they had more time to soil their temporary containers. I had promised my helpers pizza if they stayed until dinnertime and fussing over this situation pushed dinnertime past when the last of them was able to linger. I would have to reward them another day.

Lesson: If you can, set up a new tank with minimal destruction of the old. Use new Flourite, rinse it thoroughly, and arrange for at least 24 hours between putting it in the tank and whatever happens next. If possible, don’t buy new fish while a tank is still equilibrating after a major shift like this.


The dust cloud was short-lived, in the end. By the next day it was clear enough for me to tidy most of the aquascape issues, and by the day after it was almost gone. In the interim, I could adjust how various plants’ roots were buried, make sure my lotus seeds were in the right places since the fish were moving them a little, and otherwise switch from setup to refinement.

One amusing side effect of this whole adventure was confirming that I have five Amano shrimp, not the four I had previously thought. One I had not seen in months and concluded was dead turned up during the teardown of the old tank.

Another amusing side effect was the reappearance of numerous plant weights from plants that failed to thrive, revealed by the upheaval of the old substrate. Some of them have since been reused for new plants.

One less amusing side effect was that three glass/ghost catfish, Kryptopterus sp., that I purchased from the only store in town to be carrying them are currently missing in action, present and exploring their new home on Sunday but nowhere to be found on Monday. Given the Amano shrimp’s ability to hide from me, it remains possible that the fish are simply out of sight, but signs are inauspicious. The other new and old fish are happy. If indeed the glass catfish have died, I have additional tank capacity to share with a different species, in addition to what remains held in reserve for fish that were not in stock.

A school of glass catfish, Kryptopterus bicirrhis, showing their transparent bodies and long barbels.
RIP, fated attempt.

Either way, I now have twice as many fish, so I must feed more, and I am very pleased to have this problem.

Lesson: Patience has ever been my finest virtue, and my every failure to exercise it is a reminder.

What’s Next?

I intend to ascend into the planted-aquarium stratosphere that I see displayed in aquarium specialty stores, on YouTube, and in the homes of other OVAS members in the monthly web calls the club hosts. In the not-too-distant future, I will be replacing the lights currently on this aquarium with specialist planted-aquarium lights with the ideal 6500k color temperature. Depending on how that goes, I will consider a CO2 injection system, and this combination will enable me to grow more demanding plants at greater densities. I have sensibly avoided harder-to-keep plants such as the beautiful Madagascar lace plant (Aponogeton madagascariensis) before this step, but they are where my heart is headed and I shall follow when my setup is ready. One of my other target plants is Aldrovanda vesiculosa, the waterwheel plant, whose claim to fame is that it is an aquatic carnivore that feeds on planktonic crustaceans using traps similar in mechanism to those of its close cousin, the Venus’s flytrap. Aldrovanda is famously difficult for houseplant and carnivorous-plant enthusiasts to maintain due to needs that align closely with what a properly lit, CO2-injected planted aquarium provides, so this, too, is a possibility I can explore once my system is ready. My fish and Aldrovanda alike will benefit from how the space in my new, larger aquarium stand allows me to set up a smaller tank for raising live foods like brine shrimp, freshwater ostracods, or scuds, as well.

A 125-gallon aquarium showing many Java fern and other plants and some tropical freshwater fish from all over the world.
Three days later. I am no longer sure how much is lingering Flourite dust, how much is a potential post-transfer bacterial bloom, how much is the spectrum of the economy-grade lights that came with this kit, how much is condensation on the hood…but it’s clear enough to enjoy.

I have other fish acquisitions in mind, depending on what is in stock in local stores. As above, I have tank capacity to spare even after an overnight doubling of the number of fish and crustaceans in my care, and some ideas of how to fill it. I might even consider something more dramatic like a vampire shrimp (Atya gabonensis, a harmless filter feeder). In the immediate term, however, the best course is to let this system get used to itself and let the existing plants settle and grow some more, while my wallet likewise heals.

I have similar plans to set up one more, final aquarium, most likely a marine setup optimized for an Odontodactylus scyllarus mantis shrimp, but that is waiting on a delivery that should be mere weeks away by now. Time will tell.

Lesson: My ambitions are thought-out enough that I can usually get around any difficulties I might have with them, and I can pursue them at my own pace.


So there we have it: I now have a 125-gallon tank I intend to grow into a powerful testament to my green thumb and fish fingers alike, and I have plans. I hope my experience can be instructive for those of you who are pursuing similar goals or might like to.

Lessons from an Aquarium Upgrade