Mantis shrimp water parameters

[Buddro96]

Hi all,
I recently purchased a peacock mantis and set up a tank using a bottle of doctor tims insta start and biospira insta start. Long story short a week in and my ammonia spiked to 4.0ppm. I did a 95% water change and replaced all the water with nutri seawater and I used a bottle of bio spira (this time for a 75 gal) and poured it all into my mantis 20g tank. Ammonia now reads at just about 0 ppm. What should I do moving forward ? Thanks

 

[Spare time]

I use seachem prime when I have a spike in ammonia to keep it safe. Did you cycle the tank before hand (meaning you had ammonia in before you put the bacteria in)?

 

[Buddro96]

The tank wasn’t finished cycling but there was ammonia present (around .25-.75 ppm) when I added the bacteria 10 hours ago

 

[Spare time]

Im not sure why it spiked unless you just added the mantis (then that makes sense) but it doesn't always drop rapidly after adding the bacteria. I would get some microbacter7 and some prime. The olny thing I can think off is that you cycled it and then ran out of ammonia before you out the mantis in but I am not 100% sure the timeline.