GH and guppies

[Angelmarina]

I catch my GH raising up to 16 some days. I know guppies ideally prefer a lower GH but I’m wondering if they can tolerate a higher level or if this is harmful to them? I use test strips. My tank in cycled. Nitrates are now at around 10 with big water changes.

 

[Colin_T]

What units is your GH measured in (ppm, dGH or something else)?

Guppies need water with a GH around 200ppm but will be fine in harder water.
They will not do well in water with a GH below 150ppm.

 

[Essjay]

Guppies need hard water; their range is 8 to 30 dH. A GH of 16 dH is not a problem for them

Why is your GH changing? Is there something in the tank (coral, limestone etc) that increases GH?

 

[Angelmarina]

Thank you both for the quick responses. I use the tetra 6 in 1 test strips the measuremen for GH in 16d, I forgot to clarify.

Essjay you are correct. I have been adding minerals into my tank because the water is soft were I live. I was advised to do so by a friend.

 

[Angelmarina]

I am pleased to know they can tolerate this though!! Thanks so much for the help.

 

[Essjay]

The GH should not change even if you are adding minerals. Fluctuating GH is bad for fish.

The way to use minerals is to add them to the new water at every water change, adding the amount that will give exactly the same GH as the tank water. This way the GH in the tank stays constant.

 

[Angelmarina]

The GH should not change even if you are adding minerals. Fluctuating GH is bad for fish.

The way to use minerals is to add them to the new water at every water change, adding the amount that will give exactly the same GH as the tank water. This way the GH in the tank stays constant.

I do add the minerals in with water changes, however I may have increased it without realising. What do you recommend? Does this mean the water they are currently in is bad for them? It is usually between 10-16 anyway the colour on the test strips comes up between these figures.

 

[Essjay]

The steadier you can keep the GH, the better it will be for the fish.

How do you do a water change, with a bucket or a hose? If you use a bucket, the easiest way is to add exactly the same amount of minerals to each bucketful of new water. If the strips show a colour for 10 to 16 with no reading between those, it may be better to buy a liquid GH tester to measure GH more accurately - most of them measure in stages of 1 dH. Once you know exactly how much mineral to add, you just need to add that exact amount each time.

 

[Angelmarina]

The steadier you can keep the GH, the better it will be for the fish.

How do you do a water change, with a bucket or a hose? If you use a bucket, the easiest way is to add exactly the same amount of minerals to each bucketful of new water. If the strips show a colour for 10 to 16 with no reading between those, it may be better to buy a liquid GH tester to measure GH more accurately - most of them measure in stages of 1 dH. Once you know exactly how much mineral to add, you just need to add that exact amount each time.

I use a bucket add and remove water, so in future I will aim to add he same amount. You may be correct in saying I’ll have to purchase an additional GH liquid tester. I struggle to work out the exact number because the colour is never exactly 10 or exactly 16.

Have you got a particular GH tester you recommend? I am also in the UK. Thanks for your help.

 

[Essjay]

I don't have a GH tester at the moment but I used to have an API GH tester (which comes packaged with a KH tester). They work differently from most liquid reagent testers - you add 1 drop and shake the tube; add a drop and shake the tube and so on, counting drops, till the water changes colour. The number of drops = the GH in dH.
You would test the tank water, then empty the old water out. For a bucket of new water, you would add minerals a bit at a time, testing the GH as you go. Once you get the same GH as the tank, then add the water to the tank. The next bucketful is easier - just add the same amount of mineral as the last bucket needed. The first few water changes will take longer than usual, but once you find out how much mineral you need to add you won't need to test the new water as much.
The amount of old water you take out might be different at each water change so it is safer to add the mineral to each bucketful of new water as the volume of the bucket stays the same, and adding the same amount of mineral to each bucketful keeps the mineral concentration constant.

 

[Angelmarina]

I don't have a GH tester at the moment but I used to have an API GH tester (which comes packaged with a KH tester). They work differently from most liquid reagent testers - you add 1 drop and shake the tube; add a drop and shake the tube and so on, counting drops, till the water changes colour. The number of drops = the GH in dH.
You would test the tank water, then empty the old water out. For a bucket of new water, you would add minerals a bit at a time, testing the GH as you go. Once you get the same GH as the tank, then add the water to the tank. The next bucketful is easier - just add the same amount of mineral as the last bucket needed. The first few water changes will take longer than usual, but once you find out how much mineral you need to add you won't need to test the new water as much.
The amount of old water you take out might be different at each water change so it is safer to add the mineral to each bucketful of new water as the volume of the bucket stays the same, and adding the same amount of mineral to each bucketful keeps the mineral concentration constant.

I have tried a similar method before testing the buckets before adding them in. This only raised my GH because the tank strength was actually a lot higher once the new bucket was added. But I will definitely work out how much to add each time through the G tester. It sounds similar to the api ammonia tester with the liquid/drops method. Thanks again for your help.

 

[Essjay]

With the ammonia tester, you add a specified number of drops and compare the colour to a chart. With GH and KH testers, you add drops until the colour changes, there is no chart to compare the tube to. Hard water needs more drops than soft water. This does confuse a lot of people.

If your tank water hardness is, say, 16 dH and you remove some water and replace it with the same amount of water that also contains 16 dH the tank hardness will stay the same. This is what happens during the weekly water change, you replace old tank water with new water of the same hardness.
It will only raise GH if you use 16 dH water for topping up without removing water from the tank. In this case water evaporates from the tank but the minerals stay behind. If you then add water containing minerals, the mineral amount will build up and increase GH. For topping up between water changes, ideally you should use pure water such as RO, distilled or rain water.

 

[Angelmarina]

With the ammonia tester, you add a specified number of drops and compare the colour to a chart. With GH and KH testers, you add drops until the colour changes, there is no chart to compare the tube to. Hard water needs more drops than soft water. This does confuse a lot of people.

If your tank water hardness is, say, 16 dH and you remove some water and replace it with the same amount of water that also contains 16 dH the tank hardness will stay the same. This is what happens during the weekly water change, you replace old tank water with new water of the same hardness.
It will only raise GH if you use 16 dH water for topping up without removing water from the tank. In this case water evaporates from the tank but the minerals stay behind. If you then add water containing minerals, the mineral amount will build up and increase GH. For topping up between water changes, ideally you should use pure water such as RO, distilled or rain water.

I’d probably be best not using the GH tester from API then because I’d more than likely become confused to no comparison chart.

Thanks for all your help.