I dont have the $ right now to buy a sump, refugium, all the plumbing that goes along with it, pumps, etc.
Can someone just recommend what I can do to lower them without buying a sump?
Shaginwagon13- I dont mind the maintenance. Should I just continue to clean them out about every 3-4 days and still run the sponges, bio-media rings, carbon?
I wouldn't bother with the purigen and chemipure for high nitrate.
I used to run a fluval 405, and I still use it for QT. Here's what I suggest you do.
Rinse out the sponges very well, squeeze repeatedly until it runs clear. You can use RODI if you want, but I usually use plain tap water. You should do this at least once a week as a matter of routine, but you can do it more frequently for now until your nitrates are under control.
Check your ceramic biomedia ring trays. They should look dirty as a general rule, and that is normal since they are coated with beneficial bacteria, but there should be no large pieces of solidified debris. If there is solidified junk, rinse the tray in salt water, not fresh water, until clear. Do not be too aggressive here, as you don't want to wash off too much of the good bacteria.
Holw old is the carbon in your trays? If they are more than a month old, they go biologic and are also detritus traps. If they are more than a month old, replace them.
Sorry to say, but the quickest way to get that nitrate down is by water changes, You can talk to your LFS, and see if he can give you a discount on the IO salt. I suggest doing a series of 50% water changes twice a week until your nitrates are down.
Siphon the substrate and rocks when you do the water change. Invest in that contraption designed to siphon the substrate. This way, all the junk you siphon is taken out of the tank and discarded.
Later on, when your nitrates are down, you can look into getting more flow across your rocks, getting a skimmer and a refugium (you can do HOB) and
maybe removing the ceramic rings for long term nitrate control. Start planning on a sump with refugium and skimmer, and get rid of the cannisters altogether when you have the $$$.
You don't have to go too crazy. You say you have a FOWLR and nitrates are not such a big issue with this type tank. BTW what's your current nitrate level, and do you have problems with algae or cyano?