[RisingSun]

I was wondering if adding fish food without any :fish1: in the tank will fertilize plants. I want my plants to settle in first before I add any fauna. The PPS-Pro recipe suggests adding 2.5 g of dry ferts daily so I was planning on adding 2.5 g of food into the tank. However, I'm not sure if it'll work without fish.

• I'm already supplying trace elements with Flourish root tabs and P with Flourish Potassium.
• Nitrate is at 10ppm, ammonia 0 and nitrite 0. Phosphorus levels unknown.
• Lighting 40-50 par
• 48 gallon tank
• CO2 = yellow drop checker
• Plants include dwarf hairgrass, ludwigia repens, stargrass and some others

Nutrition Analysis of food:

 

[RisingSun]

Diana, you were right on the money. My plants started showing potassium and iron deficiencies on a fish food only regimen, just as you predicted. I got flourish iron and potassium which fixed the issue. Haven't noticed a Ca deficiency but I'll keep an eye out for it. I think my water is pretty hard as I get calcium deposits on the glass when the water level drops.

Fish foods have most, but not all the nutrients that plants need if you are running a reasonable stocking rate, and a low tech tank.
It is low in K, Fe and Ca. You will probably also need to supplement C.

In a high tech tank (yours) fish food should not be counted on to supply enough of all the things plants need.
I would at the very least supplement K, Fe and C (I see you are adding C- drop checker yellow).

The water should supply enough Ca and Mg if the GH is >3 degrees. If you are using mostly RO, then add GH booster to 3 German degrees of hardness.

You can use the NO3 test as a stand in for P and traces. However much NO3 you dose, then dose the right ratios of P and traces according to whatever method you are following.

If you are doing the fishless cycle, then you can work around the dosing and see what works. You should not need to dose any N during the cycle because the plants will be using some of the ammonia as a source of nitrogen. But they will need the other things.

 

[RisingSun]

The turtle I keep eats a lot and poops a lot. I have trouble keeping the nitrates (and I assume phosphates) under 40ppm even with frequent water changes. However, if there was a dry fert for dosing K and Fe without adding N and P, I'd be glad to hear it. The flourish line has been affordable and convenient for my needs.

Ammonia's always at 0 when I test. The same turtle pellets go through turtle -> tetra -> shrimp -> hidden in hairgrass carpet so I hardly see any waste.