opinion on long term tds build up

[anewbie]

So over time tds seems to increase and if the aquarium is old enough (many years) it seems to just higher and higher. The question is - is this an issue and if so why/how? Now the problem with tds is that it is composed of many different substances so unless you get a detail test of the water it might be difficult to determine the source that is causing the tds increase but it makes sense it would increase over time as pure water tends to evaporate. For example my tap tds is around 120-130; the majority of the composition is calcium and magnesium though there are other substances. Even though i do 50% water changes bi-weekly the tds has still crept up to around 220 over the past 3 years. Should i be concern?

[nabokovfan87]

On 3/19/2023 at 11:55 AM, anewbie said:

The question is - is this an issue and if so why/how?

This is OTS - Old Tank Syndrome.  Second half of the video explains what's going on and why it's an issue.

Ultimately, you can test TDS and KH/GH but you're also building up other things you can't test for.  Sometimes that's ok, sometimes it isn't.
 

 

[anewbie]

On 3/19/2023 at 3:01 PM, nabokovfan87 said:

This is OTS - Old Tank Syndrome.  Second half of the video explains what's going on and why it's an issue.

Ultimately, you can test TDS and KH/GH but you're also building up other things you can't test for.  Sometimes that's ok, sometimes it isn't.
 

 

I guess it is related but video is too high level; i mean what he sez is true but i'm being a bit narrower; we do large water changes and we can measure kh/gh and know they aren't creeping - he suggest max 50% water change but since i do bi-weekly 50% water changes (yes 2 per week) that isn't going to help. When i move in a couple of months everything will get reset and i'll be using softer water but still it becomes an open question what to do about if you want to prevent creep. It almost sounds like you have to do near 100% a couple of times a year.

[nabokovfan87]

On 3/19/2023 at 1:16 PM, anewbie said:

I guess it is related but video is too high level; i mean what he sez is true but i'm being a bit narrower; we do large water changes and we can measure kh/gh and know they aren't creeping - he suggest max 50% water change but since i do bi-weekly 50% water changes (yes 2 per week) that isn't going to help. When i move in a couple of months everything will get reset and i'll be using softer water but still it becomes an open question what to do about if you want to prevent creep. It almost sounds like you have to do near 100% a couple of times a year.

Does the tank have a lot of stone and you're seeing leeching from the hardscape? Crushed Coral in the tank?

If you're changing that much water, I'd fully expect parameters to be close to or slightly lower than the tap water you're using.

[anewbie]

On 3/19/2023 at 3:23 PM, nabokovfan87 said:

Does the tank have a lot of stone and you're seeing leeching from the hardscape? Crushed Coral in the tank?

If you're changing that much water, I'd fully expect parameters to be close to or slightly lower than the tap water you're using.

No it doesn't and i retested the tds and it was a lot lower - around 140 (tap is currently around 115); i thinking either the meter was way off or more likely it is the impact of liquid fertilizer. I think the last time i tested it was just after i did a water change and add fertilizer and maybe it didn't dillute. I'm actually ok with 140-150 range if tap is 110 since (a) I add fertilize twice a week and the aquarium is up and running 4 full years. Still I think it is something i have to study more closely to figure out what is happening (i'm speculating it was the fertilizer that made it jump to 220 and not the meter being flakey as it was a couple of months the last time i measure it). Most of this is in prep. for my move in a couple of months - as the new place will have much tighter control over the water parameters but i will be adding more fragile fishes.

Anyway thanks for hte video - it isn't that the video isn't accurate or anything it just doesn't provide an easy method of getting a grip on what portion of the chemistry is changing (I do have kh/gh/phosphate test kits and i do test these periodically though in truth nitrate is the thing i pay most attention to).