Arka myaqua400 not working correct?

[suikerspin]

Hey reefers!

im currently starting my first saltwater tank, and decided to upgrade from the myaqua380 ( without booster pump) to the myaqua400.

the water here has a tds of around 170. after installing and flushing the system for 2 hours, my TDS read 16 without the DI stage, after replacing the final stage with the resin cartridge and flushing it again, my tds doesnt wane drop below 6.

I tried reseating the membrame and that didnt work, today i reseated both the prefilter stages and the DI stage. it still sits around the 6-10. Psi is around 95-100 so theres enough pressure going in the membrame.

any ideas why its not filtering the remaining bits out the water? to my understanding the membrame itself should easily remove atleast 95% of the impurities which should put the TDS after the RO at 8 instead of 16?

edit: i bypassed the di stage, tds shows 14 right after the RO, this is still higher out of the RO, then i had when i first installed the arka380 which read around 8

 

[suikerspin]

cant edit the orignal post anymore, I opened up the resin filter, and pressed it more tightly it seems to be dropping now from 6 to 4. the resin though is already turning a darker orange,

would a tds just around 4 be safe to use to start up the tank if i cant get it lower then that? I will probaly add another DI stage or membrame next month if i cant get it lower then that to get it to 0

 

[suikerspin]

found the 2nd prefilter stage dripping, reseated it probaly 10 times keeps leaking.

so today went to the store i bought it from for both the tds and leak issues, the put some vaseline on the o-ring which looked like it fixed the leak.

Then we got into the tds mather. According to them a 90% rejection rate after the ro membrame is normal. While my previous one which uses the same ro membrame as this unit was giving me almost 75% less tds when it was new. So i told them im using the resin stage after the ro stage. And i was still seeing 6 tds. The agreed it was weird so they replaced the cartridge with another brand that fitted and was in stock.

In the store the tds dropped from 6 to 2 after 10 mins. So looked like it was fixed. Then i got home started flushing. It was at 4 for 30 mins then started slowly raising again after 3-4 hours of creating water it was at 6 again… with a little puddle of water below the unit.

Are these arka units just crap and was i just lucky with my previous unit? According to the store this is normal and these units wont reach 0 tds even with a di stage?

Im really not sure what to do with this, store just said to contact the manefacturer even do its not even a week old.

i also used the ro water with avg of 5 tds to create saltwater because my liverock would be dead rock if i waited any longer