Nathan Hill checks out a new salinity meter for the garden pond.
Now that outdoor ponds are warming and parasites are becoming rife, many fishkeepers reach for the salt. Yet, for many, this can herald their downfall.
The biggest issue when dosing salt is measuring salinity with any accuracy. This is compounded in bodies of water where dilution is only vaguely monitored, such as an outdoor pond.
It’s easy to stick in a quantity in May, but how much is still there in June, should you need to repeat dose? Many who dose salt do so blind, with little idea of the real value in their water.
This is where a salinity meter comes in. It is a small, hand-held device that’s affordable for most of us. It’s around the size of a large marker pen, and simple and fast to use. Reach down, immerse the probe into the water and just read the result from the digital display on the side.
Salt levels are either displayed as a percentage, or in parts per thousand (PPT) — the latter being straightforward enough and relating directly to grams per litre. One gram in one litre of water will give you one PPT. Five grams gives you five PPT and so on.
This takes away the guesswork and moreover allows you to tailor levels after the first dose of salt has been added.
Depending on the parasite the dose rate will vary and it’s essential that the correct dosage be followed.
The recommendations that came with the probe made me wince a bit and I’d suggest finding out the dose rates from other sources.
Apart from that, the instructions are easy to follow and the device functions as it should.
This instrument is let down only in its need for periodic recalibration. That’s no hardship — and any quality sensor needs it to stay in working order — but that means access to a standard 5PPT solution.
A code is issued for this solution if you wish to buy it from ETI direct.
ETI do a huge range of products of use to the fishkeeper and we will bring you more details soon.