So I have a heavily planted high tech 60 gallon tank that consists of Danios, Tetras, Clown loaches, Cory cats, and a couple amano shrimp. I have had this tank setup as a high tech planted for about 4 months or so. I dose full EI.
Standard gravel bought at petsmart. No CEC at all and completely inert. That is the only substrate.
No wood at all or stones in this tank that could alter GH or KH in anyway.
Dose full EI using NilocG ferts macros and micros. DIY EI Liquid Fertilizer| Premium Aquarium Fertilizer | NilocG Aquatics
So here is what is going on.
My tap GH and KH is 3 and 3. I have verified this with three different test kits. So I add 2dGH of gh booster to my tank as my Mg is extremely low at only 2 and noticed this fixed pin hole issues I was getting in some of my plants. So that puts me at a GH of 5 with KH of 3. I check this about 12 hours later and verify the GH is 5 and KH is 3. However here is where it gets weird. Now during the week it continues to rise. And I am not talking about a little but a lot. So to give you an example after 2 weeks of a complete 90% WC reset it is back up to GH of 12 and KH of 10. In fact I have not added GH booster for 3 weeks now due to me not wanting to add to the already rising GH.
I know my testing methods are correct because my 20L tank that has been setup now for about a month it stays at the levels. Meaning I add 2dGH to get it to 5dGH and 3KH. It stays this way and never moves from these levels. The 20L only has CRS in it and plants. It also gets 15ppm of co2 and half ei ferts. Again absolutely zero GH or KH creep in this tank. It has BDBS as substrate. Levels stay at a constant and have been since setup about a month ago.
The only thing I can possibly think of is food that I am feeding the inhabitants in this tank. I will list them all and post the front and back pics so maybe you can help determine if this is what is causing the issue? But even if its at all possible the food could be there is NO way it could be at the level it is.
I will post the food and how often I feed each week. The feedings are moderate and not overdone by any accounts.
Omega One super Color flakes.(Once a day)
API Bottom Feeder Shrimp Pellets(3 times a week)
New Life Spectrum Thera A+(twice a week)
San Francisco Bay Brand Freeze Dried Brine Shrimp(4 times per week)
Wardley Shrimp Pellets formula(twice a week)
Seachem Garlic Guard(Mixed usually with the brine shrimp and maybe bottom feeder pellets 3 times per week)
I will upload pics of the food after I post this.