Nitrate Spike - HELP!

[pesto]

In the past four weeks my nitrates have spiked to "40". I did a 20% water change this weekend and planning another for tomorrow. In the past three years, I have never had any reading for nitrates ..."0".


I have had several changes to my tank in the past four weeks. Would these contribute to the nitrate spike:

1. Changed from T5 to AI Sol LED lighting
2. Feeding 3 tsp/week of Roti Feast
3. Dosing 2 tsp/week of Kent Strontium & Molybdenum
4. Dosing 2 tsp/week of Kent Tech I

Here are my other readings:

1. Nitrite = 0
2. Ammonia = 0
3. PH = 8.4
4. Phosphate = .5
5. Carbonate Hardness = 12
6. Calcium = 500
7. Salinity = 1.026
8. Mag = 1500

I routinely dose using Randy's Two-Part - Alk, Cal & Mag.

What should I do other than the water changes?

 

[pesto]

Bump

 

[stingythingy45]

I don't think it has anything to do with what you're dosing.
More to do with what you are feeding and your filtration.Water changes should bring the NO3 down.

Again,your alk if that's 12 dkh is high.But,you're probably bringing that down slowly with water changes.

 

[Jocko]

Look around for detrius you can suck out. Sump/Fuge is a popular place for it to build up. That could help.

 

[gweston]

Maybe something died somewhere and it is a temporary spike? I'd stick to \water changes over a few days and see if it trends down and stays down.