30 gallons, community tank and hard water

[jaqetwist]

Hello,

since this is my first tank I am having troubles with picking the right fish for my water conditions. The tank is 30 gallons big, and it is running for over a week right now.

When I started, I measured my water and here are the values:
kH - 11
gH - 16
pH - between 7,5 - 8
NO2 - < 0,01 mg/l
NO3 - 1-5 mg/l

I want a community tank first, preferably without tampering with the water hardness.

I know that mixing biotopes is frowned upon most of the time, but I was debating putting 6-8 cories in there since I have a lot of sand in there (either pepper or bronze) with 2 dwarf gouramis (or something else for the 'middle part' of the tank) with some schooling small fishes (maybe cherry barb?)...

My head already hurts from trying to pick something out with their optimum temperatures/hardness levels in mind so help would be appreciated. Thank you for reading : )

 

[seangee]

Hi and welcome. Have you read http://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/. Mentioning it just in case because some fish shops seem to advise that just running the pump for a few weeks is enough.

Its also worth checking the pH in your tank now. Sometimes water companies mess around with this to protect their pipes from corrosion and it is not unusual to get a different (lower) reading 24 hours after the water has left the tap. Tetras and cories do well together but your pH reading is too high for most species. I keep both in water with a similar hardness to yours but a pH of 7.2. Remember its a logarithmic scale so the difference between 7.2 and 8 is quite large.

 

[jaqetwist]

Hi and welcome. Have you read http://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/. Mentioning it just in case because some fish shops seem to advise that just running the pump for a few weeks is enough.

Its also worth checking the pH in your tank now. Sometimes water companies mess around with this to protect their pipes from corrosion and it is not unusual to get a different (lower) reading 24 hours after the water has left the tap. Tetras and cories do well together but your pH reading is too high for most species. I keep both in water with a similar hardness to yours but a pH of 7.2. Remember its a logarithmic scale so the difference between 7.2 and 8 is quite large.

I will check the values again and come back here to post. I've heard it's more about keeping the pH stable than lowering/tampering with it and I would rather avoid that. It was more on the 7.5 side, it was hard to tell with the colour.

 

[Byron]

I will check the values again and come back here to post. I've heard it's more about keeping the pH stable than lowering/tampering with it and I would rather avoid that. It was more on the 7.5 side, it was hard to tell with the colour.

Adjusting pH will not be possible unless you also deal with the GH and KH, as the three are related. This is possible but not advisable, and I won't get into all that now. First thing is to confirm the numbers of your source water (which may be different from what you read in the tank water) so you/we know exactly what you are dealing with.

I am assuming your earlier numbers are your own tests; were these for water right out of the tap (source water), or water that had sat in the aquarium? And the GH and KH numbers, is that degrees (dGH or dH and dKH) or another unit like mg/l or ppm? If you can confirm these numbers with your municipal water authority, it is worth doing; check their website.

When testing pH of tap water, out-gas the CO2 first by letting a glass or jar of tap water sit for 24 hours, then test pH. This is not needed for other tests like GH, KH, ammonia, nitrite or nitrate. And your source water should be tested for all of these, on its own, to ensure you know what else you may be dealing with.

 

[jaqetwist]

Adjusting pH will not be possible unless you also deal with the GH and KH, as the three are related. This is possible but not advisable, and I won't get into all that now. First thing is to confirm the numbers of your source water (which may be different from what you read in the tank water) so you/we know exactly what you are dealing with.

I am assuming your earlier numbers are your own tests; were these for water right out of the tap (source water), or water that had sat in the aquarium? And the GH and KH numbers, is that degrees (dGH or dH and dKH) or another unit like mg/l or ppm? If you can confirm these numbers with your municipal water authority, it is worth doing; check their website.

When testing pH of tap water, out-gas the CO2 first by letting a glass or jar of tap water sit for 24 hours, then test pH. This is not needed for other tests like GH, KH, ammonia, nitrite or nitrate. And your source water should be tested for all of these, on its own, to ensure you know what else you may be dealing with.

It was for water right out of the tap. I will let it sit and measure then as well as the water from my tank. Sorry for the delay, busy with other stuff right now

 

[TekFish]

If I'm not mistaken, there are certain species of rainbowfish that prefer harder water. Some Killies also prefer harder water. Pretty much nothing from South America though, unless you fiddle with your pH and dH, sorry bud.

 

[jaqetwist]

Ok so I did the test (I know, finally) for the water in my tank, here are the values:

dGH 11
dKH 7
PH 7,5
NO3 5 mg/l
NO2 0,15 mg/l

The only thing that's in my tank is a group of Tuberculata Melanoides that is starting to multiply too much...
I believe the NO2 is too high and the cycle is still not stabilized.
Interesting is lower GH and KH than in my tap water... any idea why?


Here's a bonus picture of the tank: ceratophyllum is taking over...
https://imgur.com/a/GZCrG

 

[Byron]

The only thing that's in my tank is a group of Tuberculata Melanoides that is starting to multiply too much...

This will lessen if not almost stop when they have run out of food...which only shows how much "food" there is even with no fish. But the snails cannot live without food. This species tends to reproduce very rapidly with very few getting much larger, due to food scarcity. A lovely snail, I have hundreds, thousands even.

I believe the NO2 is too high and the cycle is still not stabilized.

Yes, you want nitrite at zero continually. I assume you are still cycling...are you adding ammonia or just leaving it for the plants?

Interesting is lower GH and KH than in my tap water... any idea why?

If the tap water GH is 16 dGH and the tank is 11 dGH...are these numbers till accurate. Plants could use some of the mineral, though I wouldn't have thought so few would use so much.

 

[jaqetwist]

This will lessen if not almost stop when they have run out of food...which only shows how much "food" there is even with no fish. But the snails cannot live without food. This species tends to reproduce very rapidly with very few getting much larger, due to food scarcity. A lovely snail, I have hundreds, thousands even.



Yes, you want nitrite at zero continually. I assume you are still cycling...are you adding ammonia or just leaving it for the plants?



If the tap water GH is 16 dGH and the tank is 11 dGH...are these numbers till accurate. Plants could use some of the mineral, though I wouldn't have thought so few would use so much.

I'm leaving it for the plants, they are growing like crazy right now. Not adding anything.
I only do ~20% water changes twice a week.

I will have to measure the tap water again, but I can't believe it changed too much in one week. Tank water is accurate tho, I just did the tests.