I was given a 55 gallon fish tank for use in an Aquaponics system. It comes with sand, large rocks for use in an aquarium, filters, a sort of magnetic fish tank cleaner, and a light. I know I won't need the filters since that will be handled by bacteria/worms and the plants and the light likely won't be needed since I'll have it by a window, but what about the other things? Is sand okay to use in an aquaponics system or the rocks and would the magnetic cleaner be useful enough to hold onto? The woman who gave me the tank thinks the rocks should be good for both salt and fresh water but I figured I'd ask to make sure.
All of the tanks in my setup were *acquired like yours -- gifted, garage sale, Craigslist, etc. It's smart and a good way to get started.
Make sure your tank was used for freshwater fish. If it was, then nothing you have is going to hurt the fish. If it was salt, get rid of everything and rinse out thoroughly. Most fish can tolerate a small amount of salt so you don't have to be perfect about it but I'd get rid of as much salt and muck as possible.
I'd get rid of the rocks -- wasted space. You need max water for fish health.
Lots of people get rid of the sand too for the same reason. I have tilapia and they like to make holes in the sand when breeding so I keep the sand.
I overstocked a couple of my tanks and I keep the filtration systems because (especially) when you're just getting started the GBs aren't going to filter as much as you'll want.
Ditch the light. Or, consider repurposing it by buying a 6500k bulb(s) and using it as a grow lamp.
I hope this is useful.
If it was used for salt water fish, would you suggest getting rid of the sand as well or just remove it temporarily for the purpose of cleaning the tank?
i don't think you can't use the sand from a salt tank. Need to dump that in the ocean ... way too much salinity there for the system to handle. I just cleaned out a 100g acrylic tank that was used for salt. After I cleaned it out there was some stubborn salt deposits. When I started to think about the epsom salts and aquarium salts I've added I decided not to worry about it. Fish are thriving, no problem.
What if the salt were separated from the sand using water to dissolve it?
You could try it but I think you're asking for trouble. Sand costs $2.50-$4 at Home Depot for 50 pounds, and you need one bag (maybe 2) to fill the bottom.
Question what type of fish are you going to be using for your system???
I was thinking Tilapia, I read they're somewhat durable to PH and Temperature Changes.
Well they don't need much for a substrate and with sand they will move it all over the tank. I had a little expanded shale on the bottom of my 55 gal tank and they push it all around especially when they are going to breed. The less you have in there the better. Easier to see the babies and keep the tank clean. Tilapia are heavy poopers just so you know. They are also very territorial and need some places to keep away from each other. I have large 7 inch long by 6 inch pvc pipe pieces of pvc in the tank but it is my breeder tank. If this going to be your main tank then the more fish you have in the tank the less territorial they become. An you also wont need the pvc pipe in there. I use it to give the females somewhere to hide from the males.
Well, do you think Tilapia fish would be okay for a beginner? I'm not really picky on the type of fish as long as it's plate sized, but I'd prefer fish that are more resilient so I have more room for error. That's why I thought I'd use Tilapia since they're said to be resilient.
I seriously doubt the salt stuck in the rocks would pose any problem. What is there would dissolve readily anyway and in conditions where we want to add a little 'slime' to our fish we salt them.
my concern would be the rocks. When I had salt-water fish, I used dolomite, which is a calcium based rock with a high magnesium content. It was great for salt water as it tended to really elevate the pH. plus taking up space is also a big consideration. what the OP is calling "sand" is likely to be gravel but if the tank was salt water, might also be crushed coral, which wold also raise the pH. Good things for salt water fish but not so good for freshwater.
I just think sand (or any substance) whose source isn't clear to you isn't a good thing to keep in a tank.