Screwed Up Badly, How Do I Fix It?

It's been a couple of days since it happened, but here goes.

For the last few weeks I have been EI dosing my heavily planted tank. Macros 3x a week, Trace and Iron 3x a week, 50% water change on the 7th day, repeat.

Friday I was getting ready to go and saw dead fish in my tank. 3 of my glowlight tetras were dead. The previous day I had found the remains of my last ghost shrimp, and my snails hadn't moved in a few days.

Tested ammonia: 0ppm
Tested nitrites: 0ppm
Tested nitrates: 160+ ppm!!

I panicked, the test vial looked like it was full of cranberry juice. I performed an emergency 80% water change and did not feed the fish or dose fertilizers. I am putting all ferts on hold for a while. Today I checked my snails... 3 of them were dead, the other 3 alive but locked up tight in their shells.

To top it off, my tank is overrun with diatoms. Some of the leaves of my dwarf sag look almost black, and plants I thought were dead and brown were just covered in diatoms. The tank is so heavily planted that it isn't feasible to remove everything or clean it all manually.

I've tried to help the fish out a bit, I brewed about 2 gallons (tank is 46 gallons) of IAL tea and added it for it's beneficial properties. It isn't much but I hope it helps. Tank is also now running dual filtration.

My light is on for 6 hours a day, with CO2. I'm considering feeding my fish only every 2 days for a while to reduce excess nutrients in the tank.

Please, if there is any advice I can get on how to fix this mess completely, I'd greatly appreciate it. I feel horrible for poisoning my fish and causing an ugly diatom outbreak.

 

My advice is only this: do not dose liquid ferts unless you see deficiencies. Root tabs go a long way. Dosing too many liquid ferts in the water column that go unused causes algae issues and nitrogen issues like you're dealing with.

Keeping aquatic plants should be done by eye, there is no specific regimen that should be followed IMO

 

The water change is a good start. I did daily water changes for about 7 days before seeing my tank consistenly down to around 30-40 ppm nitrate after the one time I realized it was 160 ppm.

 

Yes, I will do a water change to get it to the 0-20 ppm range. What is nitrates from tap?

 

The water change is a good start. I did daily water changes for about 7 days before seeing my tank consistenly down to around 30-40 ppm nitrate after the one time I realized it was 160 ppm.

Will keep that in mind, thank you. Today I discovered the rest of my snails had died...

aquatickeeper, my parameters from the tap are 0 ammonia, 0 nitrites, 0 nitrates, and no chlorine or chloramine as I am on a well.

 

What is the nitrates after the 80% wc?

 

What is the nitrates after the 80% wc?

Not sure, unable to test right now. I was thinking that the large water change would reduce it to 45-50ish ppm and that less feeding and a heavy plantload would further reduce it to safe levels.

 

Do two 50% water changes back to back to get that level down. Rotting snails definitely contaminate water real quick.