HC agm battery solution

I have a mazda 626 with stock engine and battery, my stereo consist of diamond cm3 components in the doors. I have diamond 6x9's in the stock rear, with a boston IS tweeters, and a diamond tdx 12" sub. IM powering my speakers with a 4 channel 800 watt autotek mean machine (the old black chrome ones) im also using a autotek mean machine 1500 watt amp to power my tdx sub. I have  1/0 cable going from my car battery to a distrabution block in my trunk area with the two power lead offs going to my amps. I have a 1/0 ground in the trunk area going to a distabution block in the trunk area with the lead offs going to the amps. and i have a model 400 bat cap in series with the power cable going to my 1500 watt mean machine amp. I recently got ahold of a HC power battery model hc 2200m. it puts out 12.9 volts/120 ah.  i was wondering if i could put that in series with my power cable after my bat cap and then going to my 1500 watt amp.  or vise versa. The only problem i can see besides over working my altenator, is that battery wont charge fast enough to put out what it can supply. is it even fisable to ad my HC battery in a non stock location? would i just need a high out put altenator or a second one? any help would be much appreacaited.its all good

im still working on building my knowledge but from my understanding if you install an afte market battery with a factory one you should wire it in parallel to the factory one. like i said that is what i know of. if i am wrong some one please correct always want to learn more. also i believe it would always be best to do an after marketH/O alternator to make things work nicely. just my 2 cents