What do you think?

You mentioned phosphates at some point. Did you recently test for them?after having told us you do not have an rodi water system my guess is that the water you obtain from your LFS is the source. Have you ever tested this water before adding it to your system?

 

You've gotten a lot of great advice, here. Just a few points I'd like to touch on:

1) Rocks and sand; If the nitrates were coming from them, they would leach themselves out fairly quickly with your filtration and WCs.

2) The canister; If you have mechanical filtration in it, that needs to be changed quite often as trapped detritus still breaks down into DOCs, causing nitrate issues. And if you don't, you would do much better with a reactor. The higher flow through most canisters only allows for minimum chemical filtration.

3) Last but not least, your test kit; Have you used more than one, or have your LFS test the water for you? IMOPE, a SW tank with sustained nitrate issues quickly becomes a GHA jungle, and I don't see any in your tank. OTOH, you can get false high readings from old kits/bad reagents.

Love the scape, BTW.

 

ok, just a couple of answers to questions...I have tested my water from the source and it is clean....I don't know the TDS of it but no nitrates or phosphates.....I haven't test phosphate in a while just because I assume it's low because I'm not having algae issues...the nitrates I have tested with both API and Salifert (both new test kits)....I think what I've discovered is is that I have not been doing enough large water changes because when I test trates after a water change, it makes a minimal dent in my trates...that's why I've come to the conclusion that I need to do a complete turn over or perhaps even more to bring them down.....I do regularly clean out my canister, I had already taken out the rings and only ran carbon and phosguard in it with one sponge...and I mean it when I've cleaned the sponge, there is minimal detritus that comes out - that's why I think it's got to be the rock and sand - pellets have made a dent in the trates, but I think they're just too high for it to really make a difference...I really need to make a decision on the sand, whether to remove it or keep and clean it really well.....

 

Cleaning sand won't remove bound phosphate and organics. That just tankes time and lot of critters to keep it stirred up and cycling over. And especially pristine water. I think it can take a long, long time though. in an old tank, without proper flow and filtration, everything will tend to settle into the sand and rocks, over time and accumulate and work it's was down. Algae can only use nitrate if there are other nutrients and trace elements, so, if there is some other limitation, you don't necessarily get tons of algae growth. Also, your CuC can make what's there less noticeable, as with less compute onion, resulting for higher nutrients, often more palatable algae is able to grow.

Something allng the lines of Taking the tank apart, put everything in buckets. Replace the sand, put everything back together, with 50% new water. Certainly may help speed up the process. The term "old tank syndrome" can mean a lot of things, not really, a reall thing, but there are a lot of negative effects that can compound over time, producing such a result.

Have you seen these articles yet?


Feature Article: Old Tank Syndrome — Advanced Aquarist | Aquarist Magazine and Blog

Feature Article: The "Old Tank" Syndrome — Advanced Aquarist | Aquarist Magazine and Blog

 

In terms of mixing up saltwater, is it ok to use a cleaned out plastic garbage can?

 

You could but I wouldn't risk it if its been used! I'd drop the $20 on a new one to be safe imo

 

just like a rubbermaid type plastic?...I'm mapping out "my plan of attack" now LOL