High TDS

[Garydes]

Seeking advise from expert :-
Recently i measure my tank TDS, the reading is 450, which i know is very high and very dangerous for shrimp.

1) what is the cause of this high TDS?
2) can someone explain in simple words the meaning of TDS?
3) How to bring down the TDS?
4) Can change water and replace with distilled water help?

Hope to get some advise.

[Urban Aquaria]

I'm not an expert but i've kept CRS shrimps for a while before, so can share some info on it.

TDS is Total Dissolved Solids... basically all the minerals and other inorganic substances suspended or dissolved in the water.

Usually in an aquarium the TDS rises over time, due to things added into the water and from the flora/fauna.

Higher TDS is usually indicative of harder water, its usually a concern for those who keep low pH fishes or shrimps, which also prefer soft water (ie. lower TDS). In addition, high TDS can also indicate over-feeding or an over-stocked tank.

Regular water changes help to reduce and moderate TDS (our local tap water is around 70-100 TDS), that's one of the reasons why tanks which don't change water for weeks or months tend to have very high TDS.

You can use distilled or RO water during water changes (since they have most of their mineral content removed), its a common practice amongst keepers of more sensitive shrimps like CRS.

[Garydes]

Hi senior, thanks for explanation and sharing...in this case i think is because of my overfeeding that causes the TDS to raise.
Does that means also the minerals dissolved in the water and not absorb by the shrimps?
My house tap water TDS is around 50, however after adding SEACHEM PRIME to remove chlorimate... the TDS increase to 150.

And when added to my tank it became 450....

I intended to do a 50% water change and replace with distilled water, can??

[Urban Aquaria]

Could be due to a combination of many factors, there are always excess minerals that are not used or absorbed, so TDS constantly accumulates over time in the water.

Chemicals and additives (ie. water conditioners, buffers, mineral powders, medication, fertilizers etc) all do add TDS too, so have to factor that in.

Distilled or RO water will help dilute the existing TDS levels and lower it, but if you are keeping sensitive fishes or shrimps, its better to do many small water changes over a few days (ie. 10% daily), instead of one large water change, so that the parameters don't change too drastically.