Cost: £14.99
Date of Review: 9/2/2025
The Sales Pitch from Hydro:
Looking for the best outcome of your weekend wash? HYDRO Pre is the answer to all your prewash products. A product that can be diluted down to many different formulas to work on different surfaces such as paintwork, plastic trims and even floor mats.
Designed specifically to make it easier to remove contamination from around your vehicle before doing any contact wash. A cleaner suitable for degreasing, removing grime and even suitable for removing mould from interior plastics.
This formula can be sprayed on via our spray cannon and left while you apply HYDRO Snow through a snow cannon. Hydro Pre is not citrus and therefore can be left to sit for longer before spraying off. Allow for a dwell time before agitating with a brush on the hard to clean areas such as badges and grilles.
Dilution levels:
Exterior surface; dilute to 3:1, spray on using the spray gun or nozzle, leave to agitate the grime and then jet wash off. Use a detailing brush to get into the tough to reach areas and heavy soiling. Interior surface; dilute 15:1, spray on using the spray nozzle provided, rub in using a detailing brush and wipe away with a microfibre. Convertible Roof; dilute 15:1, spray on using the spray nozzle provided, rub in using a detailing brush and jet wash off.
This product is sold with a spray top.
The special formula of this Pre means with correct dilution you can lift the thickest of grime, tar & anything else in your way. Inside and out, grime is gone leaving it safe to be wiped or washed away.
Source: https://hydrouk.co/collections/all/products/hydro-pre
What You Get:
One litre of product. The sales pitch says that this comes with a nozzle. When I purchased this as V2 Full Spray Bundle, the product didn’t come with a nozzle.
Product Description:
The product is designed to be a pre application to ‘lift’ the dirt and grime away from the paint even before a Snow foam or contact wash. The product is lightly scented and pleasant enough smell. This product is designed to be diluted outside and can be used inside which is unusual for this type of product.
Instructions:
I have an issue with the instructions. The bottle says to dilute 4:1 for exterior and 15:1 for interior. However, the sales pitch says “Exterior surface; dilute to 3:1, spray on using the spray gun or nozzle”. I have also seen a video that says dilute 6:1. Now as far as I’m concerned, the bottled product has the instructions for use I shouldn’t have to take various recommendations into account.
So I mixed my product up as per the bottle’s instructions. If the mixture is meant to be different ratio change the label, simple as that. Having three or four conflicting instructions for the same product does not fill me with confidence in the product or that the company knows what they are doing, especially when they are new to the market in March 2023.
Testing Environment:
A cold day with no wind. I was to test this on two cars that I left to be really grubby with no car wash for six weeks or so.
Application:
I carefully measured the dilution for 1 litre of prepared mixture 800ml of water to 200ml of product and mixed.
I used the V2 Hydro Spray bottle review can be found here as it was part of a bundle package.
The spray was acceptable which was applied “generously” as recommended and the product clung to the paint for a minute or so before it started to vanish running down the vertical panels. On a warm or hot day with a breeze I suspect this will be gone quite quickly and dried out.
I left this for “a couple of minutes” as per the bottle, keeping an eye on what was going on I could see that that not a lot was happening.
Removing:
The whole point of my purchase of the bundle was for days like this where a product(s) could be applied, jet washed off and left with a clean car. The expectations was high based on the hype. The bundle says that applying the ‘Snow’ over the top will then remove the debris from the paint after the Pre has lifted it.
The Hydro ‘Snow’ review can be found here.
Results:
The jet wash showed a clean(ish) car when it was wet. But after allowing both the cars to dry out the results were poor. Some of the heavier grim was removed a little, but the rest of the dirt film was still on the car. especially noticeable on the black smart car.
Before the car was allowed to dry out I used a couple of cotton pads to gently wipe the middle of the doors, not even the most dirty parts.
First was the grey Honda.
Secondly was the black Smart car.
I performed this test as on the Hydro promotional videos the guy used his finger to swipe the paint and showed a clean finger tip after the jet washing.
After seeing these results I ended up getting the buckets out and washing the cars properly. Far from the ten minutes dirty to clean that I was expecting as shown in the promo videos.
Rating: 2 out 10
There are many products on the market that are this heavy use pre wash application and mostly citrus based. The instructions on those products even say do not use repeatedly as it will strip away the wax and other protections on the car. This has product has no such warning. The product is for paint, gloss/matt wrapped cars and wheels. This suggests it not a very strong product. Even when mixed at 4:1 which is a lot of product to be honest.
Ease of use: 8 – 10
Finish: 2 – 10
Conclusion:
The results and conclusion will be very similar to Snow as this was a two step process recommended by Hydro.
There are many pre washes on the market and much more economical than this. At 4:1 this will only make up to five litres. Other products can be diluted at a ratio of 100:1 which still has far superior cleaning and you get so much more product making it a no brainer to buy the other brands.
This product is left to dwell for a couple of minutes along with being a weak product it’s not enough. The product isn’t very strong or particularly good at what it does.
At £15 for a litre it’s not the most expensive, but when you reduce the dilution up to 3:1 or possibly 2:1 it’s a very expensive product for what you don’t get in performance. If it works, I don’t mind paying for it. The recommendations to dilute this to 6:1 ratio will give you virtually no cleaning power in my opinion.
I did see a slight improvement, but nothing like what you would be led to believe or even expect. The cotton pads were filthy even after a couple of inches swipe not even a long swipe of the panel. Perhaps I should try again with a stronger mixture and update this review. ‘Pre’ had it’s chance as per the bottle instructions and failed.
This review was close to getting a 1 out of 10, but it did remove a little bit of stuck on dirt, or was that just the pressure washer removing it. I suspect the later to be honest, but I will give this a very big benefit of the doubt.
I don’t say this very often, but avoid this product (maybe the company?) and stick to the big names and established players in the market who have a good reputation.
Would I recommend it? NO
Would I buy it again? NEVER