I am helping my daughter set up her first tank.
It is a 12 gallon tank.
We bought some flourite as we intend to add live plants.
So, I rinsed the flourite and it looked like we got it running clear.
However, after we put it into the tank, it totally clouded up with what was obviously what I had missed in the rinsing.

After a few hours of running my filter, the red stuff has substantially cleared but the water looks cloudy.

Should I just remove the water and re-wash the gravel?

Any advice would help.

this cloudiness may be due to the nitrogen cycle or fluorite.i think it will be clear after some time .
NOTE:don't add fish untill the water becomes clear.

There's drops you can get that will help clear the water. They bind the particles together and make them larger, and so the filter can trap them more easily.
If you do decide to change the water but leave the gravel alone, when you pour new water into the tank, place a small dish or bowl in the bottom where you are pouring the water. This will help to not disrupt the gravel bed and prevent it from happening all over again. Or, like you said, you can start all over and rinse it much better the next time. The clarification drops harm nothing and should be safe for all types of plants and fish you'll eventually put in.
As Fox stated already, the cloudiness may be from the "new tank syndrome". From the look of your post, though, it sounds like the gravel was the cause and you've yet to put fish in, anyway.
Enjoy the new tank, most certainly she will! It'll open a world of wonder for her!
Let us know how it goes and if you have any more questions we'll be happy to help!

Thanks for the replies.

When I got up this morning, the water was perfectly clear. But I wanted to level the gravel and when I did that, BOOM, big cloud again. I am certain that this will clear again but is this normal? Or did I really mess up and not clean the gravel well.
Should I just take the gravel out and re-clean?

Thanks.

that is normal. try setting up a 75 gall. and think your filters broke and run out to replace it. boy that sucked! i would leave the gravel in there and let it filter through for a few days to a week. you can get the drops to clear it, but you want to build up the good bacteria in it. what kind of fish is your daughter wanting? fish are a good choice for kids, you dont have to walk them.

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I plan on bringing some plants in now and a few fish. If this stuff kicks up, will it hurt the fish. I believe that when I eventually vacuum the gravel, it will do the same.

Also, should the gravel be 1-2 in or 2-3? I bought 20 lbs for my 12 gallon tank.

Glad to hear its definitely sediment.
If you use a gravel siphon now before the plant roots become too established, you can probably get it mostly clean.
2-3 inches thick would not be too thick, being that your planting live plants... sounds about right.

Ok. I think we are about to get the fish and plants.
She's thinking Serpea(?) Tetra and Cherry Barbs.
Is it ok to bring in these two (let's say 3 of each?) or should we stick with one kind for now (3) and introduce others later?

But my MAIN concern is: if we kick up sediment, will it harm the fish?

Thanks for the help!

I would not do the cherry barbs, that'll limit you to the types of fish you can get later. Serpae tetras will perhaps be bullied and nipped at by the barbs. Generally speaking, barbs are not a "peaceful community" type of fish. They are pretty though and moderately active, but steer clear if you want to do tetras and live plants. The barbs may even eat the plants. As far as barbs go, cherries aren't as bad as some of them, but perhaps find another type of fish thats clearly peaceful.
The serpaes will even chase each other around a bit, but they know not to hurt each other.
Regarding your main concern the sediment won't really harm the fish at all.

Add your plants then wait day or two before adding fish if that worried about sediment, you shouldn't stir up sediment adding your fish.

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Dan & Tara
kids

flourite is place under your gravel, every time you plant or move things around a dust will appear..... not much you can do with clay..... If you want try eco complete for a planted tank.... you won't have that problem

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