Review: Mosura water chemistry range


Mosura is a big brand where fancy shrimps are concerned, writes Nathan Hill. It has a huge range of foods, chemistry supplements and an awful lot of 'curious' products currently warranting some close investigation from myself.

Armed with conductivity meters, expensive pH probes, and comprehensive test kits, I chose to take three products — Mosura pH Down, Mosura TDS Up, and Mosura Mineral Plus Ultra — to see how they behaved.

For all of my tests, I used multiple one-litre samples of water to see what effects were had. At the start, all my samples had a pH of 7.65, with 14°GH and 6°KH.

The temperature remained constant at 20°C/68°F, and conductivity averaged at 774μS.

Mineral Plus Ultra is a re-mineral product for shrimp-use RO water but can also be added to the tank direct to increase GH.

Based on pH values, at <6.3pH, 1.5ml per 10l is used. At 6.3 to 6.8pH, 1ml per 10l is dosed. No measuring device is provided, so you’ll need a syringe or otherwise to provide the correct dose. I used multiple syringes.

Added to my samples, readings were consistent. At a dosage of 0.1ml, mixed in my litre samples, the only parameters that moved were GH. It was raised 2° to 16°GH, and conductivity was lifted to 785μS. KH and pH remained as they were.

Mosura pH Down provided some unusual results from test to test and frankly needs a major overhaul for accurate dosage. Presently, the hard to measure, granular, crystalline substance is simply added to a cup of water and then slowly added to the tank 'a little at a time' in a truly unscientific way.

I used a lump the size of a 20-pence coin to make a stock mixture in 250ml of water (same parameters as sample water) and then added 5ml to my one-litre containers.

The pH certainly dropped — down to 5.5pH — and GH showed a descent to 11°GH. Conductivity dropped a little, moving to 725μS, though confusingly KH increased slightly, moving to 7°KH.

On the other hand, a high degree of discolouring in the water was noted with an orange/red tint strongly visible.

Mosura TDS Up is another in the line that needs to revise its dosage instructions, which currently amount to 'experiment a bit and see what happens…' The product claims to increase TDS and conductivity without affecting GH, though lowering pH slightly.

For TDS Up, I placed single scoop (provided in the packet) measures to my one-litre samples. The average readings of the results were impressive on the conductivity front, for sure. Readings jumped to 3435μS after a minute of mixing, with a lowering of pH down to 6.75, and a tiny decrease in KH to 5°KH. Contrary to Mosura’s claim, my GH substantially increased in all samples, to an average of 23°GH.

On the other hand, not only did the compound refuse to dissolve properly at 20°C/68°F, but it created a degree of frothing on the surface of my samples and discoloured the water as the pH Down did.


Mosura Mineral Plus Ultra did what it said on the bottle, though for me, and for anyone with a basic scientific understanding, it would seem possibly cheaper and easier to simply buy the salts required direct from a chemist.

TDS Up and pH Down disappointed me a bit with their ad-libitum approach to dosing rates. Frankly with chemicals that can influence water chemistry — and subsequently livestock wellbeing — so rapidly, I’d want to see exact dosage rates before unleashing this stuff onto people’s pets. However, in their defence, they all did roughly what they said they’d do — especially the TDS Up.

Sort out those dose rates and instructions, Mosura, and you could have a good product. But don’t leave me guessing. If I’m unsure about how to use it, a newcomer almost certainly will be confuzzled by it.

Prices: Mineral Plus 100ml bottle £14.99; TDS Up 40g pouch £16.99; Mosura pH Down 40g pouch £16.99. More info available from

Why not take out a subscription to Practical Fishkeeping magazine? See our latest subscription offer.

Don't forget that PFK is now available to download on the iPad.