Ejackal

Guys

Buying off the shelf seperate chemicals etc to make up a DIY fert is not a easy task.

Thus, I have put together a DIY Plant fert mixture made up of 2 off the shelf products - Trace Elements 100mg and Fertiliser 400mg - as depicted in the tables below in order to give me a reasonable solution to dose at 10ml/day for my 1000l tank.

A question for all you chemistry boffins out there - does the below final mixture in the TOTAL MIX table look OK and safe to use in my tank? or are there issues and/or elements I should add etc?
What about the minor Copper content?

Any help/advice would be greatly appreciated.

Eric

bradac56

I'm not sure I follow you, so you don't want to buy KN03, KH2P04, Trace (CSM+B) from one of the normal suppliers { http://www.greenleafaquariums.com/aq...ertilizer.html or http://www.aquariumfertilizer.com/in...ditU=1&Regit=2 } and want to make it yourself?

Other than that your mix looks ok, sulfur and copper seems a bit high to me but sulfur shouldn't hurt anything tho high copper could kill shrimp over time once it builds up.

- Brad

fono

It’s not recommended to mix Micro with Macro. It’s probably because it can cause a kind of nutrient lock out. If it was possible, why any commercial product sell that? Then, it is important to do not mix NPK with micro.

I add nitrogen, phosphorus and potassium in the following proportion: 75% N/ 25% PO4 / 100% K.

Ca to Mg must dose 4 to 1. Do not add if you have high GH (more than 100 ppm)

Fe depends on your plants demands. I add 0.5 ppm daily.

For the proportion of others micro you can follow the micro proportion in Flourish:
http://www.seachem.com/Products/prod.../Flourish.html

ppm recommended in your tank:
N 10-30 ppm
PO4 1-2 ppm
K 20-30 ppm
Fe 0.10 – 0.2 ppm
Ca 20-30 ppm
Mg 2-5 ppm

Regards

Guillaume

Philosophos

With this mix by the time you achieve non-limiting nutrients with macros, you'll be finding toxicity with copper in shrimp. Check the EPA ecotox database if you like; it's hard to link to its search results. Neocaridina find their LC50 with CuSO4 in the .14-.7 range depending on the study you take.

The micros should definitely be separated. Try mixing a little of the two together and see what happens

The NPK looks good preportion-wise, but personally I'd aim for the dosage of nitrogen to be around the 20ppm range; I'm looking at it around 23ppm off hand for simplicity. Half or a quarter of this for low light/non CO2 methods. I'd probably lean more towards inverting the N and K numbers, but that's just me and it's probably not necessary.

If you were to separate the micros out, I'd check your tap water's Cu levels first. You could get away with .37 iron from trace without any problems if it's low enough. Even dosing .2ppm Fe with this mix would be enough to get by in many cases, and I can't see that being much of a problem.

Magnesium might be something worth checking in to. Your micros may not contain enough if your tap doesn't have enough. The same may apply to calcium if your water is exceptionally soft.

-Philosophos