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Extra 40 pounds of gravel... Should I change out my blue or do something else with it

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I am setting up a new fish tank, and I ordered 20 pounds of sand and 20 pounds of gravel from the internet. It came, and it's really nice. BUT, then I decided to order Eco Complete, so I no longer need the other gravel. It would cost almost or completely as much to mail it back than I would get from returning the item. So....


I have blue gravel in my other aquarium, which I don't like that much. Do you think I should switch it to this more natural color? How practical is that? What else could I do so that I don't totally waste $40 worth of gravel? Any ideas?
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If you don't like the other gravel very much, i think changing it out would be just fine :)
I know what you mean, we had blue gravel in our 30g and we switched it out to sand, which afterwards looks so much better I think. Would a local fish store buy it or someone locally, especially if it's new. If you're crafty maybe you could make a decorative vase with it?

I would say make it how you really want it cause you will be walking by it every day thinking, "I should have changed it out." Unless you're like my husband and you change your mind every week about what you would like to do to your aquariums lol.
Maybe a local fish store would buy it! Thanks for the idea. I am still thinking of changing the gravel... I should talk to my fiance about it, since it is her tank too. I am not sure how to change out gravel, so I will definitely be researching that.
Its all about what you like and what you want in there as others have said.

Will say this the best way and the easiest way on the fish to swap gravel is to remove them. In fact remove everthing. Put them into a tote of water or buckets. Any decor or filter media should go in there to keep it wet. A lot of the bacteria will be on there and you want to keep it wet. Once you have everything removed then you have two options depending on the size of the tank. If it small enough that you can pick it up and carry it when drained. Then simply do that and dump the gravel somewhere you don't mind. Second if its to big to carry then you can use a gravel vacuum to get it out. You need to have one that you can remove the cup on the end. This way you just have a hose. With just the hose start a siphon and you can siphon the gravel right out with no problem. Once you have it all out then simply restock the tank with the new gravel, all the decor and fish.

I know this sounds like a lot of work but is less stressful on the fish if you try it with them in the tank. Also a lot easier on you trying to get the gravel out with everything out.
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Back when I had gravel, it never came close to being sucked out by the gravel vac.

If you have a shop vac, that will do the job VERY quickly and easily. Otherwise, you can get a big net from the petstore for $3 and scoop it out with that. Just be sure to support the net with your other hand when removing it so that you don't break it. I preferred to remove the gravel before all the water was removed, that way I could finish draining the tank once it was barebottom, getting all the gunk out. It's not really that important that you get all the gravel out - anything left behind will eventually make it's way to the surface where it can easily be netted out.

Making the switch is intimidating, but it's not difficult. Like was said, removing everything is best, and bins or buckets are the way to go as far as storing the fish while you work. Most important thing to do is take your time and not forget anything. The fish will be fine in a bucket for however long it takes for you do do the job, so don't be worried about them and rush through it.

Honestly, the last few tanks I made the switch on I didn't remove the fish, or even turn off the filter. I netted out all the gravel, let the filters clear the water, and then poured the sand in with a pitcher. Of course I THOROUGHLY washed the sand, so I was not concerned about the water getting cloudy or the filters getting damaged. That's certainly not something I would advise someone to do - that's the kind of thing you can decide to do on your own, once you have sufficient experience and confidence.
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Thank you both!

Will the tank cycle again if I keep the same (used) filter cartridge? How long until I can change the cartridge after I change the gravel? (I need the filter cartridge next Thursday so that I can set up a new tank.)
Bacteria lives in the substrate, as well as the filter. Anytime you go messing with the bacteria in your tank, it is a good idea to fast the tank for a few days afterwards, to allow things to regain their balance.

I would wait on setting up the new tank until things are square with that one.
What is fasting the tank?


The reason I need the filter next Thursday is because I am moving to a new apartment and want to set up the new tank when I get there. My existing tank is at my fiance's house, which I will see and take care of on the weekends. If I changed the gravel today, would the bacteria have time to get established in the gravel by next Thursday, so I could use the filter?

I am not intentionally trying to rush this, but my summer is sort of crazy from here on out, and I would like the look of the more natural gravel. BUT, the health of the fish is important to me, so I don't want to mess that up.
Fasting is when you don't eat. Feeding the fish only adds to the bioload of the tank - something you don't want to do when the tanks biofilter has been compromised.

Wait, so you are starting a new tank and keeping the old one? I would put the gravel in media bags (you can get them for like a dollar) and leave them in your existing tank. Once you set up the new tank, move the bags of gravel to the new tank - that will transfer the bacteria, which will then colonize the media in the new tanks filter.
So, I can change the gravel in my existing tank, keeping some of the old gravel in media bags. I keep the used filter in the existing tank. THEN, when I move, I will bring the bags of used gravel and put them in my new tank. Eventually, the bacteria from the old gravel will colonize in the new tank's new filter, and I can remove the old gravel. Did I get that right? How much of the old gravel should I save? Would a pound or two be okay?

Thank you SO much for this information! This is really helping.
Jaysee depending on the size of the gravel and the size of the hose you can siphon it out. I have done it numerous times but yeah a shop vac would do it a lot better.
Yes, you've got that right. The bacteria living on the gravel will also colonize the substrate of the new tank. It may not be enough to do an instant cycle, but it takes considerably less time for existing bacteria colonies to spread than it does for them to set up shop in the first place. Another thing that you can do is put a media bag of gravel in the new tanks filter.

What size is the old tank, and the new tank?
So, I can change the gravel in my existing tank, keeping some of the old gravel in media bags. I keep the used filter in the existing tank. THEN, when I move, I will bring the bags of used gravel and put them in my new tank. Eventually, the bacteria from the old gravel will colonize in the new tank's new filter, and I can remove the old gravel. Did I get that right? How much of the old gravel should I save? Would a pound or two be okay?

Thank you SO much for this information! This is really helping.
A pound or so would be plenty. You can keep it in a mesh bag or panty hose. Let it sit under the filter flow so it gets some water movement and you should be fine.
The old tank is 38 gallons, and the new tank is 29. I don't have a working syphon, so I will just take it out by hand. (The one I bought won't fit on the sink faucets at my fiance's house, even with an adapter. Hopefully it will fit at my apartment though! I just went out and bought four filter media bags. My apartment is a little over 2 hours away, and I won't be setting up the new tank until the night, as I will be moving things from the moving truck. I was thinking of filling up a ziplock bag with water (with water conditioner) on the day of the move and putting the media bags full of gravel in the ziplock bags. All in all, the gravel will be out of a tank for probably 5 or even 6 hours. Will the bacteria survive that?
I did it! Goodbye blue, hello natural honey color! :-D


It was a lot more disgusting than I thought to remove the gravel by hand, and I am having trouble replanting one of the plants, but I think it's going to turn out to be worth it once I add some new plants. (It looks very bare and bland now compared to the blue gravel. I am in desperate need of some more greenery!)

I left the old filter cartridge in the tank, along with about a pound and a half of old gravel in media bags. This morning I did water tests, and here's what I got:

Ammonia - I couldn't tell if it was 0 ppm or a little more. I am guessing it was around .05 ppm. The lowest reading on the key, other than 0, is .25, and it wasn't even very close to that.
NitrItes- 0
NitrAtes- 10 ppm


I don't know if the tank if going to go through a cycle all over again or if the presence of nitrates means it isn't going to. What do you guys think?
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Congrats! Now how about showing off all your hard work? We love pics!!

As long as there is Ammonia showing and there is fish in there I would do a water change once a day and use a conditioner that detoxifies ammonia. The tank might go through a small cycle but I wouldn't think it would last long.
I will post a picture. I will wait until I put in new plants, though, because the tank looks practically bare. :oops:
Yay for change though!! bet it looks great, even if its bare :)
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The water was REALLY cloudy when I first added the water, but now it is crystal clear. The new color is really nice. It just looks much emptier without some of the plants (I took out a couple that had seen better days and the biggest one is floating at the top right now, waiting to be replanted. (It was hard to see where I was planting it when the water was cloudy, so it dislodged and floated to the top.)

My new substrate is sand and fine gravel. Will the water get cloudy every time I do a water change? I am hoping not. It was very cloudy when I put the water in this time.
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