First step, already a gone bad?

Skmnri · Mar 1, 2020

Hi guys,

I picked up a used tank (rsm 250) to start my reef journey. I was planning to become active (instead of only lurking) on this forum after cleaning the tank. Sadly ive spotted something that could be bad news. Hopefully u guys can help me out.

Ive found a weird spot in the silicone in the corner of the tank. How bad is it?

do i have to be worried? Feels bad to start this way... i'm hoping that you guys are going to tell me that the silicone is thick enough in the corner.

I asked the seller to fill it and i checked for leaks, but i just missed that completly.

jtl · Mar 1, 2020

If the defect is between the glass panes as opposed to the inner seal than the tank needs to be taken apart, cleaned and resealed.

Skmnri · Mar 1, 2020

Top picture is side view, two other pics are front side.

jtl said:
If the defect is between the glass panes as opposed to the inner seal than the tank needs to be taken apart, cleaned and resealed.

Thanks for your message! Hmm, can u explain a bit more what u mean? I don't understand it. Inner seal?

The "inner" seal seems intact and it seems like a big seal. But i dont know what expect as a beginner.

jtl · Mar 1, 2020

The "inner" seal is the one in the crevice between the glass panes, sometimes it is wide and sometimes it is barely noticeable, just depends on the skill of the person making the tank. The critical seal is the one that physically hold the glass panels together and also prevent leaks. If that seal is compromised you will have major problems at some point, probably soon rather than later.

ReefStable · Mar 1, 2020

Usually, if there is an issue with the seal, it is bad news. Though it will likely hold water, these are generally time bombs. It is possible for the seal to fail and the entire tank will be on your floor...

You can reseal the tank, but I generally don't trust myself doing that. I would personally look for a different tank or talk to someone that has resealed tanks before.