Temp outside the Grobo

@vegetato, so just put both in them? How much Hydroguard should I put in please?

About 5mL is the recommended dose (2mL per gallon) for our reservoir, but I’ve found better success using 10-15mL (upwards of 20-25mL at times).

The label states to use it within 6 months of opening (or ~24 water changes) so depending on the size of the bottle you purchased you might just want to do some simple division like this:

  • 250mL bottle size / 10mL dose = lasts 25 water changes,
    • meaning it probably won’t last longer than 6 months, so not much will “go bad”
  • if you purchased a larger bottle I’d dose 15-20mL each time personally

Cheers @vegetato , I’ve got the 3.78Litre one.

In that case you’ll want to keep the bottle in a cool dark place to try to preserve it as long as possible.

I’ve found the effectiveness does start to drop off after around the 6 month mark and I’ve read reports from others online who observed a similar result with older bottles (I was using a 10 month old bottle and it wasn’t working so I went searching).

When that happens it can be offset by just adding a bit more, though, to up the concentration. You may need to double that dose in 6 months or just buy a new bottle (fyi).

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Sound, I’ve put 20ml of Hydroguard in and added GW too. She’s looking a bit better and bigger now but hopefully starts to grow a lot more now I’ve got Hydroguard.

This is what she looks like now:


@vegetato Can’t believe the difference a day with Hydroguard has made.


I wouldn’t attribute that solely to the hydroguard. She’s been picking up the pace day by day yeah? If anything it’s been helping to keep that on track.

The great white takes a while to kick in but when it does it really does!

Edit: how are the roots looking now? Noticed the temp is 25°C in the pic.

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Yeah she’s been picking up slowly to be fair but had a right boost since yesterday. Been about a week since GW been going in so with what you’ve said I reckon next few days I should see a big change then.

A lot more roots now and they are a lot thicker. It’s normally 26 degrees in there. I’ll send you a pic of the roots tomorrow so you can see if that cool?

Yeah if you didn’t snap a pic don’t disturb her just for me! When you do take a peek it’s a good idea to snap a pic for comparison vs last time.

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Hi @vegetato, the roots look like this now.

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What I’d be watching for is that the new white ones stay white. That middle section still has quite a dark spot to it, though.


Yeah I’m pretty sure that’s the nutritions from number 5 to be fair.

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Just an update on my grow now. On 14/14 transition now. She’s had a couple of hair cuts. Gonna wait another week maybe before a give her another trim, what’s your thoughts???