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fertilizer fish tank water for fertilizer?

Edmick

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I have a 60 gallon freshwater fish tank and I've heard that theres alot of nutrient in the waste produced by fish. I do not add any chemicals to the tank whatsoever so im just wondering if when i do water changes, will that water be beneficial for my plants? Does anyone else do this? Thanks
 
   I've never personally tried it, but I do know a man who owns a greenhouse. He has a similar setup to what you're describing. He uses the fish waste water on his plants, and has been very successful. I say give it a shot. If you're concerned, just try it on a couple test plants first.
 
 
    Tim
 
The only issue I see is ph. The ph in my tank runs over 8 but I can adjust that no problem.
 
Yea i was thinking of it as just a supplemental fertilizer. I only do water changes on my fish tank every two weeks and i fertilize twice a week so it would just be supplemental to the fertilization schedule i already have.
 
I couldn't imagine having that high a ph in my tank. Mine averages 6.4-7 ph. I don't use my fish tank water because i'm lazy but I do use my ponds water because it's right by the garden
 
I dont really pay much attention to my tank. The sucker fish keeps the algae off the glass and the water is clear. Thats all i care about. But now im starting to think that regular water changes might benefit both my tank and my plants! Lol
 
take a look at aquaponics system so you will understand whether you need other fertilizer or not. don't add anything unnecessary. 
 
Works like a charm.
 
IMG_20170506_082613.jpg

 
I have only used it on one big pot , because it is just under the window where my fish live , so it is very easy to syphon water with a hose . It is also the only pot that receives no other nutrients and it really thrives.
 
Having run an Aquaponics system for for 5+ years I can tell you fish water will provide a little N and P.  Most systems lack in K and micro's.  This is especially true for heavy fruiting plants that use a lot of K.  A good quality fish food designed for AP will supplement P, K and micro's...normal flakes don't provide much.  By all means use the fish water.  If I take the time to gather worms and feed my bluegills the plants really love it.  I also keep worms in the grow beds to help break down the old roots and waste.  When I had tanks I usually let the solids settle out in the bucket and used the top water for pots.  The solids got dumped in the beds to avoid smelling bad.    
 
Edmick, how did the fish tank water plan work out for you? My daughter has a small 10 tank that I clean out ,no algae eater fish (they kept croaking),we got snails to eat the algae. I’ve been using it on my OW plant I haven’t killed it yet. [emoji16]


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PtMD989 said:
Edmick, how did the fish tank water plan work out for you? My daughter has a small 10 tank that I clean out ,no algae eater fish (they kept croaking),we got snails to eat the algae. I’ve been using it on my OW plant I haven’t killed it yet. [emoji16]


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As Rairdog said above, it only gives a small amount of N and P. I tried growing chillies with pure aquaponics, and had a massive fail, the only stuff that grew well was lettuce. There is definitely enough nutes for some greens, but if you want your plants to fruit you'll need to feed them something decent.
 
PtMD989 said:
Edmick, how did the fish tank water plan work out for you? My daughter has a small 10 tank that I clean out ,no algae eater fish (they kept croaking),we got snails to eat the algae. I’ve been using it on my OW plant I haven’t killed it yet. [emoji16]


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I have not tried it yet to be honest. I have a ton of plants going this year and i'll have pepper plants planted all over my property. I'll reserve a little spot for plants that I will water exclusively with fish tank water and let you know how they do.
 
karoo said:
Works like a charm.
 
attachicon.gif
IMG_20170506_082613.jpg
 
I have only used it on one big pot , because it is just under the window where my fish live , so it is very easy to syphon water with a hose . It is also the only pot that receives no other nutrients and it really thrives.
 
By the look at those "cupped" leaves...they lack calcium. I wont hurt to make them produce at optimal rate by correcting the deficiencies. Impressive bush nonetheless!
 
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