to much nitrite is there a quick way right now to lower them and 50% change to much

hello to some you will all know my situation. i have a 180 with to many huge fish and adiquite filtration. im dividing all the fish up once the 1500 gal. is complete in a couple weeks after cycling the tank. but all of a sudden i did another 50% water change the other day and they started breathing a little heavy. i was worried all day so i added some aquarium salt to the water as well as my pro Ammonia Blocker that i use with every other change. i have been doing around 50% water changes every week sometimes more and i never have had a problem with the nitrites spiking as they are. i was so shocked in the levels when tested at around 1.0! i ran around and took additional filtration off of all ready running tanks and put them on the 180, changed out more water, and added salt to the tune of 1 table spoon per 10 gallons of water replacing. I checked the levels at 2pm after the change and salt it was at 1.0 still, i checked it at 7 pm still 1.0 checked it this am at 7 and it was still 1.0 im nervous about my fish and am looking for answers. i will do another change tonight unless instructed otherwise but i am really hoping instead of finding a way i can lower them safely without the hour long trip to the fish store tonight. these guys are the biggest and the best of the stock, cant kill em now!! oh and also i was worried that with the additional load in the tank, i had to much matter in the bottom everywhere i was not pythoning every week and moved everything from one side to the other to clean it front to back with not much change in amount of material.

please help,

any advice will be great.

hey great idea but i have well water, i already had that thought and tested the tap strait of from open to after it has run for a few min and there was no ammonia. tell me more about the removing of mechanical filtration? i thought that the more filtration the better by being more area for the good bio to have grown? as for a starter, i have always liked the kents pro ammonia. it protects the fish from so many things that could change and makes tap water safe. i do have some bio safe start left i could try next time now without filtration wouldn't the bad go to worse on hours? or not?

awesome info thankyou so much i have the temp consistently at 78 and have kept it there sense winter at least. also i have three 18 inch air strips and filtration from a hanger that adds some air as well. i will not worry about the salt as much if it really is not much of a help and i think im going to stay up a while longer and clean the canister filters all out and do a 75% change tonight with my safe start after it. i replaced all the filtration in the hanging one but not the canister. thankyou again im keeping you posted.

yes they are, i have a reaction four that i received with the tank 5 months ago. i have replaced all pads shortly after and just cleaned them all again. when i do water changes i typically change around 50% i do the changes weekly most of the time but sometimes more often. i tend to vac the gravel every 2nd or 3rd time and get rid of the crap. i also was running a 400 gph 90 on it until recently once i set up my ninety in the basement i moved that filter down there. this is where i went wrong i think. this increased demand on the crappy reactor 4 uv filter and as i just found out, plugged it. the filter i just took apart i had to tilt the trays to drain so you can only imagine what it was doing for the water. now i put a 350 gph 70 gallon three layer hanger on it and all new parts in this one but old beads. because i was going to take both filters apart i did the 75% water change as recommended and put everything together and she is running again and full. everyone is looking better however one of the hybrids still breathing a little heavy. its late so im going to leave them alone and test it now then am and see where i am at. hopefully the clean media, the same coat on everything necessary and 75% new water im hoping it will be good to make em feel better in a bit. thanks for all the help we will see in the am and get there pool filled this week to start cycling until then if i have to i will change water every day. oh and tank has two 20" redtails 2 10" redtails and four 5 inch oscars. this is why im going with the 1500 for just the cats and the 180 will be simply oscars.

aaaahhhhhhh. .25 not all gone yet but huge improvement of 12 hours ago, will check in the am