Advice With ATI Results

bevo5 · Dec 16, 2021

Like so many - I'm dealing with a brown sand issue on one side of my tank. I posted a thread a while back because I had raised my nutrients up but the issue was persisting, so I thought maybe it wasn't dinos. My new plan is to lower nutrients to see if that helps - and I sent in a sample to ATI.

The results were fairly good - but I show a very high level of aluminum (105.7 µg / l) and of course the high nutrients. Nitrate (34.23 mg / l), Phosphate (0.20 mg / l). I need to lower those.

For the RO water - everything was good except silicon (1146 µg/l), which was then normal in the tank itself (95.94 µg / l).

So my thinking is - maybe the silicates are getting into the tank and feeding the algae, which is why the silicon level in the tank is ok?

I have a Spectrapure RO unit and I replace the filters fairly often - whenever the TDS goes above 0. It's reading 0 now, but clearly something is getting through. Should I be more proactive in changing out the resin or something? What removes silicates in that system?

Beyond that - should I worry about the aluminum?

I'm going to do a series of water changes to lower nutrients (slowly) - but I'm just feeding silicates into the tank at this point.

Any other advice?

Thank you all.

rtparty · Dec 16, 2021

You should have gotten an RO result with ATI ICP. What did it say?

0 TDS doesn't really mean much because like you are noticing, things get through that don't have an electrical charge and therefore the TDS meter doesn't pick them up.

The aluminum isn't hurting anything. Do you have any type of ceramic media in the tank?

The brown on your sand could be diatoms from the silica or it could be dinos. Not all dinos recede because of higher nutrients. You are likely fighting dinos and it is from a lack of biodiversity. Dry rock sterile tanks suffer from this for quite a while IME.

bevo5 · Dec 16, 2021

rtparty said:
You should have gotten an RO result with ATI ICP. What did it say?

0 TDS doesn't really mean much because like you are noticing, things get through that don't have an electrical charge and therefore the TDS meter doesn't pick them up.

The aluminum isn't hurting anything. Do you have any type of ceramic media in the tank?

The brown on your sand could be diatoms from the silica or it could be dinos. Not all dinos recede because of higher nutrients. You are likely fighting dinos and it is from a lack of biodiversity. Dry rock sterile tanks suffer from this for quite a while IME.

Thank you for the reply.

Yes, the RO result showed everything was good except a high level of silicon - 1146 µg/l. So clearly my RO unit isn't stopping that and needs to be adjusted. I'm just not sure if that's an RO membrane issue or a DI resin issue. I replaced both probably 3-4 months ago, but I do run a lot of water through.

The microscope test I did looked very much dinos but with no movement or spinning or anything. Just round cells. I figured I've tried high nutrients, so I was going to try lowering them down. The issue will disappear for months then come roaring back - always on the same patch of sand.

I did use dry rock - and I've been adding phyto and live rock to try and get some diversity in there.

Randy Holmes-Farley · Dec 16, 2021

bevo5 said:
Thank you for the reply.

Yes, the RO result showed everything was good except a high level of silicon - 1146 µg/l. So clearly my RO unit isn't stopping that and needs to be adjusted.

Can you show the RO results?

Silica gets through RO/DI easier than most things, but enough DI capacity will eliminate it.

Not sure if that's needed though. Unless the problem is diatoms, there's no worry.