Question about water hardness

[Randomflutterby]

Hi all, I have a mystery that I can't figure out with Google.

My tap water is pretty soft, (3 general harness), as is a new tank I just filled. The weird part:
I have a 10 gallon tank I took over a few weeks ago from a friend. The gh has been 8ish the eye entire time I've had it.. Water changes and all. Why is the water in there so hard?


Thanks

 

[Colin_T]

I assume the numbers for hardness are dGH and not ppm?
3 dGH is about 54ppm, which is very soft.
8dGH is about 143ppm, which is soft.

Something in the other tank is making the water harder. It could be shells, limestone, dead coral rubble, mineral salts, gravel or something else that has been added. The tank might have been getting harder water and it hasn't diluted out yet in the time you have had it.

Pictures of both tanks might give more information. Also a description of the filters and what's in them.

 

[Randomflutterby]

I assume the numbers for hardness are dGH and not ppm?
3 dGH is about 54ppm, which is very soft.
8dGH is about 143ppm, which is soft.

Something in the other tank is making the water harder. It could be shells, limestone, dead coral rubble, mineral salts, gravel or something else that has been added. The tank might have been getting harder water and it hasn't diluted out yet in the time you have had it.

Pictures of both tanks might give more information. Also a description of the filters and what's in them.

Yes, dGH.
The filters are tetra whisper quiet (one 20, one 30-60 I believe I'd have to look again) with carbon cartridges ( I plan to replace them eventually with media, but I don't want to crash my little tank)

10 gallon is the one with the fish, 36 gallon is empty ( I'm cycling it so I can move the bristlenose... I'm aware a 10 gallon tank is easy too small for him. I didn't buy him)

 

[Colin_T]

The only difference I can see in the tanks would be the gravel. Perhaps get a bucket of tap water and check the pH, GH and KH. Write the results down. Then add some gravel from the 30g tank to the bucket of water. Let it sit for a week and then check the pH, GH and KH again. Compare the results.

You can move the old filter onto the new tank and move the fish straight into the 30g. Then cycle the smaller tank or take half the filter media and put it in the other tank. There's no point cycling a second tank when you have an established one.

 

[Randomflutterby]

The only difference I can see in the tanks would be the gravel. Perhaps get a bucket of tap water and check the pH, GH and KH. Write the results down. Then add some gravel from the 30g tank to the bucket of water. Let it sit for a week and then check the pH, GH and KH again. Compare the results.

You can move the old filter onto the new tank and move the fish straight into the 30g. Then cycle the smaller tank or take half the filter media and put it in the other tank. There's no point cycling a second tank when you have an established one.

Yea I'm probably going to do that. I didn't realize I could until a few days ago ( fairly new to this hobby). Do I need to raise the hardness/ PH in the new tank to match the old one? Or just acclimate them? I know swordtails like harder water in general.

 

[Colin_T]

I would remove 10 gallons from the 30g tank. Then transfer the water from the smaller tank into the bigger one. Move the fish and filter across. Then refill the smaller tank with dechlorinated water.

Make sure the bigger tank doesn't have ammonia or nitrite. If it does, drain it completely, then move the water from the smaller tank across. Move fish and filter across. Top up both tanks with dechlorinated water.

 

[Wills]

In the second picture near the BNs tail are they shells I can see? If so thats what could be making your water harder.

Wills

 

[StevenF]

GH tests for calcium and magneisum. Often this are in the form of carbonates. The KH test measures dissolved carbonates. But calcium and magnesium carbonate are generally a solid at high PH levels and Generally only dissolve in water with a PH less than 7. It would be helpful to know what your KH and PH Also is anything being added to the during the water change like a fertilizer or KH booster or PH down? Also do yukons what the locations are made from? If they are cement that would have calcium carbonate in it. Some natural sedimentary rock are loaded with carbonates.

Overall having solid calcium and magnesium carbonate in the tank is generally not bad since it will buffer the PH helping to keep it near 7.

 

[Randomflutterby]

Yea it's probably the added things in the gravel .

One other question though. Since the tap water is so soft, should I add a bit of crushed coral to it? I'm thinking I'm just gonna move the bristlenose and get some tiger barbs for the big tank. Since the Gh is only 3, would it be better for it to be a bit higher to help with PH balance?

 

[Essjay]

If there will be only a bristlenose and tiger barbs in the tank the hardness is OK at 3 dH and a pH under 7.