How do I clean an aquarium before filling it?

In My Humble Opinion
1

So, a few weeks my daughter wanted a small fish tank. I picked up a small 2 gallon bowl that came with an integrated light/filter. It’s been doing (more or less) fine, but because of the way the light/filter snaps on to the top and because I have a small heater also hooked on to it, it’s a real PITA to do anything that involves getting at the water. That means, I haven’t really done any kind of real water changes (I’ve scooped a quart out and replaced it (twice), the thought of attempting to clean the gravel hasn’t even crossed my mind.

Anyways, I told her that if she has any real interest in these fish for a few months, I’d upgrade her to a bigger tank. She doesn’t…I kinda do. I have some bigger tanks from when I kept lizards, but I’m not sure how to clean them to ready them for fish, if I decide to go that route.
I have a regular 10 gallon tank that housed crickets and has been in my garage for the last 5 years…incidentally, the garage also managed to house a bird and a opossum during that time, the evidence from at least the bird remains (but appears to be on the outside).

I have two 40 gallon tanks that had bearded dragons and water dragons in them. Since then, they’ve just been in my basement and used for random storage.

I also have a 100+ gallon, but that’s not getting used for anything right now. Too heavy to move and I’m not ready for something that big. Besides, I’d like to try my hand at saltwater and I’ll use that one for that.

Anyways, when I told her I wanted to wait until summer to move to the big tanks, that was partially so I could use the hose to clean them out, maybe I’ll still do that. In the mean time, how, exactly, should I go about cleaning these to make them safe for fish. I can’t imagine going at them with soap or any kind of chemicals is going to be a very good idea. I’ve read a few random things on the internet, but I thought I would just start here.
Any ideas?

I’m still not sure if I’m even going to take this project on or not, but I’d like to start gathering information.

The next thing I need to do is see how much a decent stand for a 40 gallon tank is. The 10 gallon could go on her dresser, but if I go with the 40 gallon, all I have is a wrought iron stand which I don’t care for.

2

is there anything currently living in the tank? if so, you can vacuum the gravel which is just doing a water change (don’t do more than about 1/3 at a time) but sucking debris out of the gravel at the same time.

3

It doesn’t take much to build a solid aquarium stand. A 40 gallon tank will weigh about 320 pounds full, which is heavy, sure, but your bed weighs more than that with two people in it. Aquarium stands at stores are woefully overpriced.

Most places recommend first hosing the old aquariums out, then scrubbing them with dilute vinegar, then hosing them again, and again for good measure.

Are the tanks sturdy enough to handle that kind of load from the water? I think that tanks exist that are too thin to bear the weight of the water, but fine for lizards and the like. Check out what you’ve got.

4

I had one of those at one point for another project. I’d imagine by the time I got it primed and moved it over all the gravel, I’d have lost more then a third of the 2 gallons. Also, this is the tank the fish are in, there just isn’t a lot of space to work with at the top without dismantling the light/pump and heater.

5

Overpriced or not, it’s a lot cheaper then 40 gallons of water on my floor. Besides, they look a lot nicer then a bunch of 2x4’s slapped together. Either way, I don’t build things, so we should just that to rest. I’m damn good at fixing things, but when it comes to building stuff (especially from wood), it just doesn’t work for me, I’ve found it’s not worth my time.

The 40 gallon tanks appear to have quarter inch thick glass walls (didn’t look at the bottom) with (still soft) silicone sealing the edges and a plastic top and bottom. When I got them, I just grabbed them from the area with all the other fish tanks.

6

OK. Just thought I’d throw it out there.

If you bought it from a place selling fish tanks, you should be alright. Consider getting a more secure top than the wire mesh ones that I often see on lizard tanks. A better air seal will help reduce evaporation.

7

It sounds like you have aquariums. Not many glass terrariums are made since the market is much smaller. Clean with vinegar. A metal stand should not cost much, but you need to find the right size. Stubborn stains can be removed with bleach, just make sure to thoroughly rinse and let air dry. Don’t leave the bleach sitting on the silicone, I don’t think it will be very harmful, but the silicone is kind of important for keeping the water in the tank. When I used to have tanks all over the house some of them were on old wooden cabinets that I reinforced internally, or cabinets I made from old computer racks for disk drives, which you can readily find in the 1980s. You can make your own stands out of wood, but the most important thing is to make sure they are not at all rickety. Either construct them as solid as carpenters work bench, or sheathe a basic wood frame in plywood.

And definitely re-use those tanks. I only bought one brand spanking new tank. The others were ‘blems’, new but unwarrantied because of chips or scratches, or used.

Oh yeah, fill it to the brim with water for a leak test for a few days before starting to use it to keep fish.

What size 100 gallon do you have? A lot of those are display tanks and a bitch to maintain and clean. You don’t want a tank that you can’t reach the bottom of with your hand.

8

White vinegar and a brand new BLUE dish scrubber will clean the glass. Rinse as many times as it takes to get most of the vinegar smell out. The gravel should be washed by rinsing it a few times with pure water, but only enough to get the worst of the debris out. The bacteria that adheres to the gravel is good for the ecology of the tank.

A good undergravel filter, (used along with an external, if you like those too), will keep the water clear indefinitely as long as you don’t overstock the tank.

9

A reverse flow undergravel filter is best. You’ll clean your gravel once every other blue moon. It helps oxygenate the water as well. There was one manufactured that used simple air stone lift tubes to do the job (to lift the water to go down an another tube in the middle). But it’s easy to make them using plastic egg crate, plastic screen, and power heads or the output of a canister filter. You can add a prefilter on top of the tubes to keep things even cleaner. I’d never do anything else again if I get back into fish keeping.

10

+1 on this. I believe you said they had been sitting in your basement. There is a very real chance that the seals may have deteriorated.

11

I just wanted to add that rock salt or even lots of table salt makes a good scrubbing compount if you have algae, etc to clean off. Be sure to use a sponge or scrubber that has NEVER had ANY soap in it.

12

I worked briefly for a chain of discount pet stores and we used plain salt to scrub tanks.

13

I found that my 10-gallon tank killed fish too easily, even though I only had 4 small ones in there. Those small tanks really need frequent water changes, at least once a week, due to the sharp rise in water toxicity.

I had a great Python brand vacuum I used to vacuum the gravel, and a scrubber sponge to wipe the glass. I cleaned my 30 and 40 gallon tanks once every 3-4 weeks. I gave them away because 2 tanks are too much trouble to maintain. One day, I would like (1) 75 gallon freshwater tank.

14

A 2 gallon tank is miniscule, and not really suitable for fish at all- especially if you can’t do water changes… that’s going to be really unstable.

The bigger the tank, the easier it is to maintain, and most people suggest starting with a minimum size of 20 gallons. I really hate it that shops sell tiny tanks as beginner or kids’ tanks- I suppose it just means they can sell more fish when the first ones inevitably die. A 2 gallon tank is suitable for some small shimp, maybe, but nothing much else.

15

When I was in grammar school (and that’s back before silicone glue in aquariums, (they were sealed with tar glue) I had several aquaria and terraria at home, and maintained the aquarium and terrarium at school. I never had issues with ten gallon tanks (even though larger ones are better all around and the small ones were less forgiving).

I’ve always used under-gravel filters, and when they weren’t available, I made them out of whatever I could scrounge. If you have the right amount of gravel in a tank, with a good under-gravel filter and a powerful air pump, and you let the bacterial balance gradually attain an equilibrium, a ten gallon tank will run cleanly with just addition of distilled water (to compensate for evaporation) for months with no vacuuming or water changes.

I’ve had them up for years at a time, with no water change. It’s about having the right balance of fish, invertebrates (if you like them, snails) plants, and gravel. If the bacteria in the gravel are healthy and you don’t OVERSTOCK the tank with fish, a ten gallon will do OK. A two gallon is much harder, but I’ve had them be successful, too. You can’t put much in one of those.

16

So, last night I was doing a partial water change (which, as always, is a PITA). At some point I either bumped the knob on the heater or it broke because a few hours later I noticed the tank temp had dropped. That’s another problem with this tiny tank. It can swing 10 degrees in, literally, 15 minutes. If I hadn’t checked on it, it would have dropped down to about 58-60 degrees over the next hour or so.

I told my daughter if she was still interested in the fish come summer, that I would set up one of the big tanks. That was partially because I didn’t want to dump a ton of money into this for her not to care about them. But also, I wanted to be able to get the tank all hosed out on my driveway. Seemed that would be easier then doing it in the basement.

But, I’ve already got the tank, so I guess the big investment is out of the way. Maybe I will start getting it up and running.

I can get it rinsed and scrubbed (w/ vinegar) in my basement over my floor drain. Then I suppose I can fill it at least halfway with water and let it sit for a few hours and make sure the seals are still in tact.

I’m going to be near the pet store after work. So I’ll check out prices on stands. I’ve got a wrought iron one that I don’t like and it seems like it would be really top heavy once it’s full.

What else do I need? 200w heater (or 2 100w heaters in case one breaks).
Undergravel filter? The kind that hangs off the back? Bioballs? Some combonation of them?

Is a light necessary or just for looks? I’m not sure exactly where it’ll go. It’ll be near a window, but not in front of it. No direct sunlight.
Now for the big question…do I go all in and do saltwater? It’s what I’ve actually always wanted to do. I’ve read books in the past about saltwater aquariums but then when I was all ready to pull the trigger, for one reason or another it just never happened…maybe I’ll go that route. Like I said, when it comes to fish, saltwater is what I’ve always wanted to do. The challenge is something I’m up for.

17

Missed the edit.
Unless 40 gallons is too small for saltwater.

18

I haven’t looked at aquarium supplies in decades, but I’m sure under-gravel filters are still available. I can’t imagine a home aquarium without one. Now, I’m talking freshwater aquariums, here. Saltwater tanks are a whole 'nuther level of
hassle, so I only handled freshwater.

19

Okay, got a stand for a halfway decent price. I cleaned the tank and it’s currently sitting in my basement with about 6 inches of water. As of right now it’s holding just fine and I don’t foresee any issues with it.

I picked up a HOB filter since they were running (what I presume was) a great special on them. The filter is oversized, but it was cheap and it seemed better to be oversized them undersized. Also, I had been talking to the guy about cichlids and he mentioned that if I’m going to do that, I should definitely go on the bigger side. It also has two filters inside of it which gives be the ability to replace on at time. Also the guy suggested taking a handful of the gravel from my small tank, putting it in a mesh bag, and tossing it in the new tank to get the cycle started (before adding fish).

Next, heaters. I didn’t buy one there because the ones they had were considerably cheaper on Amazon (same with the testing kits).
From what I’m reading, a 40 gallon tank will need about 200W of heating. I’m planning to use two heaters to accomplish that. My question is, what happens if I have too much wattage? Will I burn out the heaters if they cycle too fast? I only ask because, with the one’s I’m looking at, 100W is $30 and 200W is $28. Or at least it was this afternoon, now they’re out. But 100W and 150W are the same price. I assume, then, I’m probably safe to just pick up two 150W heaters.

The next thing I need to decide, and I need to decide it in the next 24 hours is where to put the tank. But you can’t really help with that.

After that, I have to decide what I’m going to put in it. Or rather, do I want to do a cichlid tank or go for something with more variety.

I’m sure I’ll have more questions, but I’ll start with these.