No, more specifically, the silicone leaching toxins. I bought the tank and the sump used, so I have no idea on the history of either, and suspect one of them may have had copper. But just a guess after ruling out anything else I could think of.

Are there any studies regarding the silicone?

I'm sure there aren't, not really something that would qualify for funding :)

but, there's lots of discussions about not using tanks previously treated with copper, so I assume it's a possible scenario. I know that silicone can absorb methylene blue, so the likelyhood of it absorbing and leaching back Cu is pretty good, IMO.

Carbon has been used for MANY years, however it's still a big unknown. I stay away from it. My own preference, but works for me.

Try running without carbon for a bit even, carbon leaches out many trace elements that we need. Unless you have heavy LPS/SPS combo it shouldn't be an issue. I have 20+ SPS and 15+ LPS in my tank and only run carbon once a week for 24 hours(when i remember :S). I've had excelent growth on all my SPS, even some hidden away from good lighting.


As for the silicone thing, copper attatches itself to anything and everything it can, doesn't take much. They used to make mirror's by evaporating copper onto glass, and it would bond. I could only imagine how much gets onto the glass after dosing :S

Well, there are studies regarding how plasticizers affect invertebrates, so it's certainly possible.

The reality is that our tanks are SO concentrated compared to the corals natural environment, any so called small problem is amplified many, many times.

LOL, we all think our corals grow slower than everyone else's.

Definitely check for stray voltage if you haven't already done that, it's a good place to start.

Do you have good polyp extension and color? STN, RTN? (we are talking SPS here aren't we)

To give some idea of what a natural growth rate is (for a table acro, anyways), here is a link to a National Geographic article that shows a reef in the Phoenix islands.
This reef suffered a bleaching event in 2002 and the author went back in 2009 to find a table acro that had grown 4 feet in the 7 years since the bleaching event.
How many of us have 7 year old acros that are 4 feet across?:smile:

Given enough room, there are probably a few tanks out there that the corals could come close, so I don't think we are all that far from being fully successful raising corals.

Gives you an idea what type of growth you could be aiming for, anyways.

I've had several colonies that would put on an inch of growth in a month, so given the room and absence of fragging, I think we see similar growth in some tanks

but unless the other tank is exactly the same, with the same liverock, same coral etc, it is impossible to point this to the aquarium and silicone. I would very much doubt it. I would more suspect the liverock leaching something or coral relaesing toxine.

If you put all the same liverock, with the exact same coral with the same exact skimmer and filtration etc, salt, parameter with only the glass and silicone being different and then your coral started to grow, only then I would suspect the tank itself. But is it really exactly the same? same liverock? same exact coral? same positioning in relation to flow?

Did I miss the part where he answered how much flow is in the tank or did that get passed over? I've had acropora sit almost dormant for over a year until I put them in an area of higher flow. Then they suddenly exploded with growth and and lit up with color.

Also, have you tried any brown coral? Its common knowledge that ugly brown coral grows like a weed while colorful, limited edition, super expensive etc does squat. lol (joking... sort of)