Having Tank Issues With Water

[PorterG]

Hello. I've had this 20 gallon tank for about 2-3 years. I typically add about a gallon or so every week, and everything seemed fine till about 6 months ago. Every time I looked to add fish, they died in an hour. Over the last month I've been replacing about 2-3 gallons every day to every other day. I've suctioned the gravel, so, pretty clean. I got rid of an old plant that probably had a lot of dead leaves. I have two live plants in there right now. I've replaced 25% of the water a few times. I've added a bubbler. But, the water quality isn't changing. In some respects, it has gotten worse. The PH had been just under 6, now it seems to be dropping down to the low 5s and even into the 4s. Ammonia will spike up, then drop down depending on the day. Water quality is hard. Nitrates are high, nitrites are low. Alkalinity is low. Almost everything in the tank were decorations that were there before problems. And all purchased at a fish store.

I only have 4 fish left, 2 Golden Gouramis and 2 Australian rainbowfish. They seem to be doing well, not seeing poor behavior or body issues. Not hanging at the surface gulping air. But, after all the water changes, things are getting worse, it seems. The tap water, which goes through a filter, seems just fine when I check it. PH is about 6.25. Ammonia zero. I've tried adding different stuff, like PH up and tank water products.

I really don't want to start fresh, but, getting close. Any ideas? I've tried reading different stuff, thought the water changes would help.

 

[PorshaF]

Do you dechlorniate water before adding and add same temp water? Have you tested the tank water and not just tap?

 

[Essjay]

Can I ask you to clarify something, please.

You said you add 1 gallon every week - do you mean you remove 1 gallon and replace it with 1 gallon of new water, or do you mean you add the 1 gallon without removing any water first. In other words, are you doing weekly water changes or just topping up?

If you mean topping up, how often did you do water changes before the 2 to 3 gallons every couple of days for the last month?


The way you wrote things makes me wonder if you've been topping up and not doing weekly water changes. This leads to old tank syndrome where the water conditions drift away from those when the tank was filled. The fish in the tank acclimatise to this slow change but when new fish are put in the tank, the water conditions shock them and kill them.
The pH and nitrate levels do suggest old tank syndrome. Without water changes to remove them, acidic things build up in the water. These use up the KH and the pH drops. Nitrate is the end product of the nitrogen cycle, and without water changes this builds up. We now know that we should try keep nitrate below 20 ppm.


When a tank suffers from old tank syndrome, the remedy is daily small water changes - they have to be small as large water changes will shock the fish used to the poor conditions. After a couple of weeks larger daily water changes can be done until the tank water is the same as tap water. Then weekly water changes of at least 50% will keep the water conditions similar to tap water.




But if you have been doing regular substantial water changes, old tank syndrome is not the problem and we need to work out what could be happening.

 

[PorterG]

Do you dechlorniate water before adding and add same temp water? Have you tested the tank water and not just tap?

I check the water from the tap, and there is really no chlorine in it. Using test strips on the tank shows no chlorine.

 

[PorterG]

Can I ask you to clarify something, please.

You said you add 1 gallon every week - do you mean you remove 1 gallon and replace it with 1 gallon of new water, or do you mean you add the 1 gallon without removing any water first. In other words, are you doing weekly water changes or just topping up?

If you mean topping up, how often did you do water changes before the 2 to 3 gallons every couple of days for the last month?


The way you wrote things makes me wonder if you've been topping up and not doing weekly water changes. This leads to old tank syndrome where the water conditions drift away from those when the tank was filled. The fish in the tank acclimatise to this slow change but when new fish are put in the tank, the water conditions shock them and kill them.
The pH and nitrate levels do suggest old tank syndrome. Without water changes to remove them, acidic things build up in the water. These use up the KH and the pH drops. Nitrate is the end product of the nitrogen cycle, and without water changes this builds up. We now know that we should try keep nitrate below 20 ppm.


When a tank suffers from old tank syndrome, the remedy is daily small water changes - they have to be small as large water changes will shock the fish used to the poor conditions. After a couple of weeks larger daily water changes can be done until the tank water is the same as tap water. Then weekly water changes of at least 50% will keep the water conditions similar to tap water.




But if you have been doing regular substantial water changes, old tank syndrome is not the problem and we need to work out what could be happening.

Unfortunately, mostly it was replacing water from evaporation, while replacing a couple gallons by emptying and refilling once a month. Old tank syndrome is what I'm concerned with, have never had this problem before. Been replacing 2 gallons a day/every other day for about 4 weeks now, and around 4 gallons a few times. And doesn't seem to be getting better. PH seems worse. Do you think I should do about 3-4 gallons each time now? Or just 1 gallon a day? Worried that I keep doing this for months and nothing changes, and do not want to kill my very big, very awesome fish. Thanks.

 

[Essjay]

Use nitrate as an indicator. Test both tap water and tank water. Tap water level is what you are aiming for in the tank.

If tank is still a lot higher than tap, daily 2 gallon water changes for a week, then daily 4 gallon water changes for a week. Test nitrate before doing the water change a few times to see if it is dropping.
At the end of the second week, if it's roughly the same as in your tap water you can start doing 50 % changes once a week. If it's still a lot higher you need more daily water changes but increase them to 6 or 7 gallon per water change.


With old tank syndrome, the danger is changing too much water at the beginning. As the tank water conditions improve, bigger water changes can be done. Nitrate is not the only thing which builds up, but we have testers for that so we can use it to assess the general state of the water. Once nitrate is just about the same as tap level, everything else should be the same as tap level. The pH should then stabilise.

 

[Colin_T]

Chlorine test kits don't always pick up chloramine in water. Contact your water supply company by website or telephone and find out if they add chlorine or chloramine. You can also ask them what the pH, GH and KH are in numbers, and what measurement they use for the GH and KH (eg: ppm or dGH or something else).

Check the tap water for pH, GH, KH, ammonia, nitrite, nitrate if you can. Your tap water might have a low pH, which will stop the tank's pH going up.

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The best way to treat old tank syndrome is by doing water changes and gravel cleans every day for a month. Start off small 10% each day for a week, then 20% each day for a week. Then 30% each day for a week, Then 40% each day for a week. After that, do a 50-75% water change and gravel clean the substrate once a week.
Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

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Clean the filter if it hasn't been done in the last 2 weeks. However, if the filter is less than 6 weeks old, do not clean it. Wash the filter materials/ media in a bucket of tank water and re-use them. Tip the bucket of dirty water on the garden/ lawn. Cleaning the filter means less gunk and cleaner water with fewer pathogens.

Established filters should be cleaned at least once a month.

 

[PorterG]

I appreciate the suggestion. Unfortunately, been doing water changes and PH is getting worse. Down to low 4's at this point. Instead of rising it is dropping. I'm close to just moving the fish to a smaller tank, where the water is good (tap water and been running for 2 weeks), then starting fresh in the big tank. It's frustrating

 

[Slaphppy7]

I appreciate the suggestion. Unfortunately, been doing water changes and PH is getting worse. Down to low 4's at this point. Instead of rising it is dropping. I'm close to just moving the fish to a smaller tank, where the water is good (tap water and been running for 2 weeks), then starting fresh in the big tank. It's frustrating

It's a good lesson on the importance of weekly water changes

Water Changes and Water Quality in Aquariums – Advanced Aquarium Concepts

advancedaquariumconcepts.com

 

[PorterG]

It's a good lesson on the importance of weekly water changes

Water Changes and Water Quality in Aquariums – Advanced Aquarium Concepts

advancedaquariumconcepts.com

Can't disagree. Came home yesterday and PH spiked to around 6 from around 4. Replaced 2 gallons. Was around 5.95 this morning. Hopefully will stay good and get better. I'm wondering if the Aqua Clear Bio Max Filter caused a problem. Took it out Wed morning.

 

[Slaphppy7]

Aqua Clear Bio Max Filter?

Do you have a link, not familiar with that one

 

[PorterG]

Aqua Clear Bio Max Filter?

Do you have a link, not familiar with that one

Aqua Clear 30 Bio Max Filter Insert | fish Filter Media | PetSmart

Aqua Clear 30 Bio Max Filter Insert at PetSmart. Shop all fish filter media online

www.petsmart.com

Still staying around 6.00 PH for the moment, ammonia is not spiking

 

[Slaphppy7]

Ahhh, I see, just pre-bagged BioRings....did this come with the filter?...usually, the Aqua Clear filters come with biobeads instead of rings, and a net bag, that you had to assemble yourself...but they may have changed that packaging, it's been a while since I've bought one.

They are just inert media, don't cause tank issues, unless they've been contaminated somehow...

 

[Slaphppy7]

What kind of test kit are you using?

 

[PorterG]

Ahhh, I see, just pre-bagged BioRings....did this come with the filter?...usually, the Aqua Clear filters come with biobeads instead of rings, and a net bag, that you had to assemble yourself...but they may have changed that packaging, it's been a while since I've bought one.

They are just inert media, don't cause tank issues, unless they've been contaminated somehow...

I tried putting back in the filter, PH seems to be fine