Planning and Transitioning to 500 Gallons

Planning and Transitioning to 500 Gallons

It has now been over a year since I started making plans to change tanks from a 300 to 500 gallons. As with just about everything time related, it went fast. As I wrote in a previous article, proper planning is in my opinion, essential for the long-term success of a tank. In this regard, I wrote down, and organized just about everything I thought I would need to do and everything I thought I would need in order to successfully get this new tank up and running, while producing minimal disruption to the old tank’s inhabitants. However, I must admit, that one thing I really did not plan as in depth as I should have, was the transition process itself. I did plan some things, but as with just about everything in this hobby there has always been one more thing to do in order to get things completed in the way that I wanted. I would love to say that it has been flawless or even that it is all completed, but it is moving along. So what I hope to do in this article is point out some of the things I did right as well as the things I did wrong or that added to the process that has made the transition not as simple and seamless as I would have liked.


Planning for the new tank by acquiring the desired equipment and having it rest inside a replica of the tank.

Moving an entire tank of fish and corals from one tank to a larger tank has been one of the essential aspects of the hobby for as long as I can remember for many of us. Face it we all want bigger. Over the years I have done this transition a number of times, so you would think I would have it down to a science. While I did better than I have in the past, I still made some mistakes that I will point out that will hopefully reduce the likelihood of you from making them should you take on a project like this. The first thing to do when planning on this move and the transition is to have a plan and write everything down. I filled a tablet with plans, ideas, things that needed to be done, equipment I wanted and also notes on what was going on in the old tank and things I planned on changing. Some of them were simple, like changing from six Radion lights to eight and from three ReefBrite strips to two. Other changes were not quite as simple and easy to implement such as designing the plumbing so that fewer pumps and powerheads would be used, but flow would be increased and actually getting the flow to be as strong as I desired. So needless to say there were lots of changes along the way.


A replica of the new tank making it sure it fits in the allotted space. The new electrical outlets can be seen around it.

The first aspect of planning the transition for this change required several steps. First, as is my nature I wanted the new tank to be as large as possible and so I not only measured the available space, but once the space available was determined, I actually built a replica of the tank out of wood to make sure it would fit in the available space. This replica also proved to be critical in that it also allowed for me to make sure that it could be brought around a corner in the basement that would be required before it got to its final resting place. Amazingly when Bob Elder of Tropical Aquariums delivered the tank, he was not overly alarmed once I showed how the replica tank moved into the house. I should note that I cheated and made the replica 2-inches bigger in each dimension when I built it to make sure that it could be brought in without taking out a wall. However, I should also note that despite the planning for this transition I forgot to account for one thing: how to get the old tank out once the new tank was in place. This was an oversight because unlike transitions like this that I had done in the past, this new tank was not going where the old tank was but was instead going to sit adjacent to the old tank and after the new tank was up the sump would rest where the old tank was.


The old tank with the top off and the water starting to be drained.

Due to space limitations and how much space the new tank took up, my initial plan of removing the old tank intact and selling it had to be scrapped. Also once the tank was drained I realized that eight years had been tough on it and the stand, so in good conscience I could not have sold it to anyone anyway. This then brought up the dilemma of what to do to get the old tank out of the house. I have cut apart old tanks in he past, but never one as large as this 300. Getting razor blades and putty knives in between the glass to cut through the silicone had been a pain, but with a tank this big it really was a concern. Fortunately, I mentioned this to Karen and Bob and they said it was actually simple. Just cut through the silicone with piano wire. That seemed simple enough, until I tried to find a single strand of piano wire. This proved difficult as people thought I wanted to use it for garroting someone or something else unseemly when I tried to buy it. Fortunately, I was able to find an 18” cheese cutter that had piano wire between handles available. This device allowed me to “saw” between the glass and as a result it took less than 30 minutes to completely dismantle the tank and remove it from the house. Unfortunately, the big glass plates were heavy and unwieldy and were not readily taken by the trash company. So when you are planning something like this, also plan ahead as to what you need to do to get rid of things like these plates of glass as well as the wood from the stand. Because of this poor planning this glass and old stand filled a bay in the garage for over a month before they found a new home.


The containers holding the corals and the floor covered in towels to reduce water damage to the floor.

Planning something as simple as where to put the old tank or the glass from it was just one part of the transition. As mentioned one of the other aspects was to make this tank more user friendly and easier to maintain. In this regard, one of the things that had frequently frustrated and annoyed me with the old tank was how the electrical aspect of the tank had been set up. Actually it was not really planned or set up with any grand design, but was instead added to constantly which meant that as some new electrical device was added a multiplug or extension cord was added to make room for it. Needless to say this was inefficient, unsightly, and even worse dangerous. When everything was taken down and reorganized no fewer that seven extension cords were in use along with 8 multiplugs. Just as dangerous all of this equipment was running on three 15- amp circuits, which tripped far too frequently. So before this new tank was set up, 3 new separate 20-amp circuits were added to the room so that it would no longer be necessary to use any extension cords or multiplugs in the entire system. After analyzing, planning and diagramming and figuring out what could be cut out and how things could be done more efficiently the 37 items that needed to be plugged in were reduced to a current manageable number of 24. This may still seem like a lot, but as was the case with the 300, in addition the the main 500-gallon tank, this system also has a frag tank and nano tank attached to it. But these are being run in a more efficient manner after a lot of planning.


An idea of why it takes so long to fill a tank with RO/DI water, but it is worth it.

Having done the electrical work ahead of the move, made the transition from tank to tank relatively easy. However, there were some hiccups along the way. Since the 500 was going to be placed where the frag tank and nano tank were when the 300 was up, it was necessary to move them to the garage before the new tank was moved in. This was relatively easy and took approximately 6 hours to complete. The two were combined with one common sump and were set up for approximately eight weeks this way. There would not have been any problems if the weather had cooperated, but unfortunately major heat spells in late August and September caused the garage, which is not air-conditioned to heat up and this resulted in the loss of some corals and frags. So even though I planned for the transition to occur in the time frame when the temperature was most likely to be temperate, a curve ball wrecked these plans and heated the tanks up more than was supposed to happen. Fortunately, not everything perished, but enough did to make a dent in the coral populations in both tanks.


The new tank slowly being filled with RO/DI water. Tedious to watch.

Planning and executing the moving and placement of the new tank and having the electrical system in place were just part of the transition and for the most part they went smoothly. In fact the actual transition of the coral and fish from the 300 to the 500 went smoothly as well. Having done this before I had a pretty good idea what it would entail, but it was still a physically and mentally taxing endeavor to undertake. But for those of you that have not done this here is how this change was done. When the new tank was dry and empty and in place the powerheads were put into their desired positions and the racks, which would hold the lights were placed in their desired locations. This was done as it is easier to place them when a tank is empty rather than once it is full of water. Once this was done the next step was to fill the new tank with RO/DI water. This was actually the longest and most tedious part of the whole process. Even with a 90 gallon per day unit it took over 5 days to fill the tank. On the fourth day, when the tank was over half way filled, the salt was added, 400 gallons worth, and the the remaining water was added to bring the tank up to a salinity matching that that of the 300, 1.026. I should note that before taking this reading it was clear that the water in the new tank was significantly cooler than it was in the 300, so 2 250-watt heaters were added to bring the tank up to an equal temperature. Once the salt was added, the powerheads were turned on to mix the salt and so that the flow could be more easily visualized. Once the salinity and temperature were matched between tanks, the powerheads were allowed to run for a couple of days. This also allowed the caustic nature of newly mixed saltwater to diminish.


The old tank drained showing how much detritus had accumulated over the years.

The plan was to use only a small portion of the water from the old tanks. I know there has been some controversy about doing large water changes, but I felt that the water in the old tanks were not where I wanted it to be so I was confident that doing what amounted to a 75% change would not be deleterious. The day before moving the fish and coral both tanks were tested and in addition to salinity and temperature, the parameters including alkalinity, magnesium, and calcium were made equivalent. In planning the move, I allowed for it to take at least twelve hours, so the move was to be done on a Saturday morning starting at 7:30 am. This way even if things went sideways I could work into the night making the switch. From past experience, I had found that the key to making this kind of move was to keep things as stable as possible throughout the move, especially temperature. So the day I chose the weather was cooperating and in the mid-70s, so the temperature throughout the house was stable. So hopefully this would keep the temperature in the holding vessels stable too.


A garbage can full of the accumulated detritus.

Since the corals and fish were going to be moved from tank to tank, it was first necessary to move the corals from the tank into holding containers so that the live rock could then be moved into the tank as a base and then the corals could be placed on them. Before this could be done however, the wooden hood above the tank had to be removed. This process required removing all of the lights as well as the plumbing and wires that were all around and on the hood. Once this was done, it was much easier to get to the corals and live rock and move them into containers. Fortunately, one of my other collections in addition to corals and old towels are large plastic tubs. So for the first part of the move, water from the 300 was pumped into several tubs and then all of the corals were removed from the tank and placed into the tubs. If the corals were attached to live rock, the live rock along with the coral was placed into the tubs as well. During this procedure any pests or unwanted hitchhikers were scrubbed off the coral and rock with wire brushes. This whole process took over three hours to complete. Once the coral had all been removed and was in the tubs, the live rock was then pulled out from the tank. Most of the live rock in this tank was attached to fiberglass rods but there was still a significant amount of loose rock. During this process I found that there was a significant amount of small pieces of live rock that acted more as detritus traps than serving any other function and these small pieces were either thrown out or placed in their own container. I should also note that for this new tank the live rock to be used was mainly just the rock from the old tank, which weighed approximately 300 pounds when it was originally placed in the tank. An additional 100 pounds of rock would also be added to the new tank, and it had been curing in the garage for two months prior to it being added to the new tank.


The new Ecotech MP 60s put in place to provide movement across the top of the tank.

As the old live rock was removed, it too was carefully examined and any unwanted pests were removed and scrubbed scrubbed from the rock. This process was the most difficult part of the whole transition as pulling out these large heavy structures while reaching into the old tank, cleaning them and then placing them in their desired location in the new tank was a lot less fun than I remember it being. It also took an additional four hours, which was an hour more than I had expected. Also, as often happens when this live rock was moved into the new tank it made the tank cloudy so it was difficult to place it exactly where I wanted it to be. But I kind of planned for this, so the goal was not to have everything perfect on this first day, but more to get it all into the tank and have the tank be stable.


Tunze Stream 3s to provide flow across the bottom of the tank.

Once the live rock was in place I had to decide if I wanted the next step to be removing the fish and getting them in the new tank or putting the corals in place first. I could choose, as there was still plenty of water left in the old tank and for the most part it would remain stable while the corals were added, but as I expected it was really dirty. So at this time the corals from the various containers were added to the tank and placed in locations that I thought would be conducive to their health until they were placed in their final desired locations. That is light loving corals like Acropora and Stylophora were placed high in the tank, while less light loving corals like Montiporas and Pavonas were placed lower in the tank. This was one of the fun parts of this move as once I started doing it the tank started to take shape and it began to look like something other than the empty tank/blank canvas it started out as. This process took around two hours, so now I was nine hours into the move.


The cheese cutter that made cutting apart the old tank easy and fast.

The next step of the process was to catch the fish out of the 300 and move them into the new tank. The goal of this was to not only move the fish, but also not to stress them or to remove their slime coats and make them more prone to ick. I was especially worried about this with the many tangs I had in the tank, especially the only Powder Blue and Maculiceps I have had that I have been able to keep ick free. So in order to catch all of the fish first the water level in the tank was brought down to less than a foot. While this was being done, all coral, rubble or anything else that could provide a hiding place for the fish was removed. Once this was done, two large water pitchers were employed to remove the fish. As is usually the case the fish tend to try and hide along the sides of the tank. Using two pitchers I was able to drive them into one of the empty pitchers so that they were not stressed as much as they would have been in a net and as a result little of their slime coats were removed. This took a little longer than would have been the case with a net, but they all came through it without there showing any ick or other diseases or stress as a result of the move. Also I should note that I forgot how fast and how how smart fish are at avoiding capture. This process took almost two hours and that was for about only forty fish.


The temporary sump in action.

Once all of the livestock was in the new tank, the next goal was to get the lights going and to get a temporary filtration system set up. Since the corals could go without light without much trouble, filtration was first. The filtration would only be temporary at this point because the full sump and filtration system would go where the old tank was, and even I was not crazy enough to plan on moving the old tank out on moving day. A forty- gallon tank was used as a sump and it was big enough to hold the Vertex skimmer that would be used in the final filtration system. The overflow was in place, so it was temporarily plumbed so that it would feed the new sump. It was temporary in that rather than it being glued, the pipes were put in place with Teflon tape wrapped around them to hold them firmly in place. The pump to feed this system was also not as big as the pump that would eventually be used. So to provide water movement between the tank to the sump a Vectra M-1 pump was chosen. Since this was a temporary arrangement, the flow from it to the tank was via a flexible hose rather than being hard plumbed. Once set up it actually worked very well and since the tank was still initially cloudy a filter sock and carbon were employed to clear the water as quickly as possible.


The new lighting system set up and adjusted while the tank was dry.

I was now at the twelve-hour mark and the lighting still had to be set up. Six of the Radions had been removed from the old tank and the two new ones were already in place above the tank. So the remaining six just had to be attached to their tracks and the transition for the most part would be done. Amazingly this went very smoothly and took less than 30 minutes. Once they were all in place they were lit and the new tank actually looked like something. However, once they were lit it was apparent how open the top was and if I have learned anything, it is that any opening for fish in a reef tank is an open invitation for them to jump out. So despite my thinking I was done I, decided to build screens to cover the top. So for the next hour three screens were built and put into place and the move was done. I even had time to throw in some food, which the fish attacked as if they were in their old tank.

Before concluding I should note a couple of things. All of the fish and corals survived the transition and were good the next day. However, three days later 4 of the big coral colonies all bleached. In my haste to move everything I did not take into account that the new Radions were 3 inches lower on this new tank and that I placed these corals slightly higher up. As a result, the higher light bleached them. Duh. So take this into account when moving things. Once I saw this the light intensity was reduced from 85% to 55%, which was what an equal PAR reading was. Also to my amazement, not having the lights in a hood but instead mounted above the tank significantly reduced the temperature of the tank. In the old tank with the hood, the water temperature at the time of the change was 80.4. The day after in the new tank, after running the lights all day, the temperature was 76.5. Needless to say this dramatically reduced the necessity for cooling the tank. Also one of the more enlightening things I learned as a result of this move was that despite my doing regular water changes and trying to remove as much detritus as possible, when I cleaned and drained the tank I found almost 20 pounds of detritus that had settled out among the rock. Needless to say that is one of the reasons why I tried to make the layout of the new tank as open as possible with as much flow as possible.


The new tank right after the move from the 300. Cloudy but for the most part everything survived.

Getting the new tank up and running in two months after it was moved into the house, may seem like a long time, but I did my best to make sure that everything was done right when it was finally done. The tank is now almost fully set up and there are a few extra bells and whistles on this tank, that I will talk about in the next article, that I hope will make its long-term maintenance easier than my past tanks. Having only been playing with the tank fully set up for less than a month it is still too early to tell if the changes made will make a difference over the long-term. However, I already have enjoyed one aspect of the tank as much as I thought that I would. Having all of the equipment out from under the tank and where I can easily work on it and maintain it has already made me enjoy this tank more than most of my past tanks. Having every piece of equipment where I can easily adjust it, move it around or see it working really has added to my enjoyment of the tank and greatly reduced the time taken away from enjoying the tank that was necessary when the equipment was difficult to work on. All tanks are works in progress, but transitioning from one tank to a bigger tank is always more work than we expect. But planning not only the finished product but also the transition is something we all should do to add to our enjoyment.
About author
Mike Paletta
Michael Paletta’s actual career is working in genomics in breast and colon cancer for Genomic Health. He has been an avid reef keeper since 1984. He has kept personal reef aquaria ranging in size from 20 gallons to 1200 gallons and has helped set and build other reef aquaria up to 4,000 gallons in size. He currently maintains several reef aquaria including a 300 gallon sps dominated tank and a 75 lps tank. He has also consulted for The National Aquarium in Baltimore as well the Pittsburgh Zoo and Aquarium.

Michael has published over 100 articles on various aspects of reef keeping in SeaScope, Aquarium Fish Magazine, FAMA, Practical Fishkeeping, and Coral Magazine. He has also published two books: The New Marine Aquarium and Ultimate Reefs. Michael has been invited to speak at various venues around the world and across the country and has given over 200 such talks.

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