Fish tank water good or not

Was just wondering if fish tank water can be used when watering plants, there must be micro nutrients in it…

I wouldn’t. There are so many different parasites in fish waste that I wouldn’t want that in my soil. What’s more, unless it’s a salt tank and you’re using a skimmer, you’ll have a good bit of ammonia from fish urine in there too. What’s more, if it’s a fresh water tank and you’re using decorative stone and objects, you have no idea what chemicals are leeching into your water either.

I simply would not do it.

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I do, constantly. Growing Cannabis in fish water aquaponic style is a great way to get good tasting bud.

@TacoMac, Ammonia will turn into Nitrates to help feed the plants, along with the Nitrogen already within, and a bit of Phosphorus that was in the fish feed. The stones and aquatic (non-organic) accessories within a fishtank are food safe, and most organicly grown cannabis, that was grown Aquaponicly are safer than store bought premixes. Known chelates within normal store bought premixes like FeEDTA are known to be toxic and are still commonly used. You’re simply miss-informed.

I use it in Aquaponics along with the first feedings of clones in soil and throughout soil grows.

I will say, there’s a lot of chemicals added to fishtanks that are carcinogens and might effect the fish, but shouldn’t effect the cannabis plant. This is why most aquaponic growers are totally organic.


Have never tried on marijuana, but it makes garden plants explode!

Now I need a fish tank lol. I been lookin for a reason to get back into exotic fish looks like I fpund the perfect harmonious reason.Love it and I will have fish which will give me something to do beside stalk my plants and molesting. them thruout the day lol sounds bad but we are just talking about plants so I will touch them wherevr I i want to lol stoned and 4 in the mornig delirious

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Fish tank water is great for plants!!
Fish tank water is no more detrimental than teas peeps make and use.
If you have access use.
Recycle - Captn Planet

I siphon the water from the undergravel filter, and it’s awesome for anything I’ve used it on! Just note though, only use water from an established tank with an active, established biomass of beneficial bacteria. Taking water from an overloaded tank with high ammonia levels is no good.

Good point !!!
Healthy fish = Healthy fish water!!