Hey guys, long time user but created this new account as my old email got lost in a void. I recently bought a 300 gallon glass tank from a local guy in town. Awesome deal on it, and beautiful tank, but it had a problem. Guy said the tank was filled last year up to the 3 overflows with no issues, but was unsure if it needed a re-seal. I have it out back in the man cave shed with a concrete foundation. I’ve had a lot of tanks and ponds in there so I knew it could hold the weight. I went ahead and filled it slowly over a couple days to make sure no leaks were found. Once I got it full I left it over 2 days and checked in on it today. The “industrial tank silicone” completely split on one end of the tank and drained the entire tank onto my man-cave floor. Clearly needs a re-seal at this point, but what silicone does everyone suggest? I can get some casual aquarium safe silicone, or GE Silicone 1. I’ve done some research on the topic but I wanted suggestions of those here that might have tanks just as big or larger than mine. Is there anything I should special order for a tank that size with that much weight in water? Any help would be appreciated, thanks!
300 Gallon Disaster
- Thread starter Arowamazon
- Start date
The easiest way I know of to check if something like silicone will react with anything (or in this case leach chemicals into the water) is to check what it's made of and check each of its ingredients. For this I searched 'GE All purpose silicone 1 SDS' to find it's safety data sheet. In it the SDS warns against 3 ingredients other than silicone. Silicon Dioxide, Methylsilanetriyl triacetate and Triacetoxyethylsilane, we can google each to check what they are and if they're poisonous to fish.
Going to echa.europa.eu we can find dossiers for both Triacetoxyethylsilane and Methylsilanetriyl triacetate and their toxicity to fish. In this case Triacetoxyethylsilane was found to be toxic over 180mg/l and Methylsilanetriyl triacetate at >110mg/l. So let's say the chemicals have to stay under 10% toxic levels
Based on the findings from echa.europa.eu, Triacetoxyethylsilane and Methylsilanetriyl triacetate can be toxic to fish at concentrations of 180mg/l and 110mg/l, respectively. Although these concentrations are relatively high, it's always safer to stick to products specifically labeled as 'aquarium-safe' to avoid any risk of leaching harmful chemicals. If you're unsure, I recommend choosing a 100% silicone product that's known to be safe for aquarium use.
BTw tagging some members who might provide additional info or have experience
jjohnwm
wednesday13
Backfromthedead
Going to echa.europa.eu we can find dossiers for both Triacetoxyethylsilane and Methylsilanetriyl triacetate and their toxicity to fish. In this case Triacetoxyethylsilane was found to be toxic over 180mg/l and Methylsilanetriyl triacetate at >110mg/l. So let's say the chemicals have to stay under 10% toxic levels
Based on the findings from echa.europa.eu, Triacetoxyethylsilane and Methylsilanetriyl triacetate can be toxic to fish at concentrations of 180mg/l and 110mg/l, respectively. Although these concentrations are relatively high, it's always safer to stick to products specifically labeled as 'aquarium-safe' to avoid any risk of leaching harmful chemicals. If you're unsure, I recommend choosing a 100% silicone product that's known to be safe for aquarium use.
BTw tagging some members who might provide additional info or have experience
jjohnwm
wednesday13
Backfromthedead
Awesome! Thank you for reaching out. I always just assumed GE silicone 1 was safe and non-toxic for fish. I’ve seen a lot of YouTube videos use it including Tanner over at SerpaDesign. I usually trust his videos more than othersThe easiest way I know of to check if something like silicone will react with anything (or in this case leach chemicals into the water) is to check what it's made of and check each of its ingredients. For this I searched 'GE All purpose silicone 1 SDS' to find it's safety data sheet. In it the SDS warns against 3 ingredients other than silicone. Silicon Dioxide, Methylsilanetriyl triacetate and Triacetoxyethylsilane, we can google each to check what they are and if they're poisonous to fish.
Going to echa.europa.eu we can find dossiers for both Triacetoxyethylsilane and Methylsilanetriyl triacetate and their toxicity to fish. In this case Triacetoxyethylsilane was found to be toxic over 180mg/l and Methylsilanetriyl triacetate at >110mg/l. So let's say the chemicals have to stay under 10% toxic levels
Based on the findings from echa.europa.eu, Triacetoxyethylsilane and Methylsilanetriyl triacetate can be toxic to fish at concentrations of 180mg/l and 110mg/l, respectively. Although these concentrations are relatively high, it's always safer to stick to products specifically labeled as 'aquarium-safe' to avoid any risk of leaching harmful chemicals. If you're unsure, I recommend choosing a 100% silicone product that's known to be safe for aquarium use.
BTw tagging some members who might provide additional info or have experience
GE Silicone I is the product that has been considered the standard for aquarium use for many years; it was produced before that under a different name, but the idea was that it was supposed to be "pure" 100% silicone and safe for our purposes.
The thing is...it's all BS. There are any number of silicone sealants that are marketed as being 100% pure silicone, but which contain anti-mildew agents and who-knows-what-else, so by definition they are not pure.
I've gone through numerous case lots of Silicone I over the years, both for building all-glass tanks (mostly smaller tanks, 50 gallons and under) as well as for sealing and adhering glass panes into larger plywood tanks. I also run a bead of it around all inside seams of plywood tanks as insurance, and use it for all kinds of smaller aquarium jobs as well.
I understand that there are other silicones available that produce stronger bonds, and which would likely be preferable for actually building larger tanks, but I've never looked into them personally because I don't need that kind of performance, and I try to avoid fixing things that ain't broke.
If I had built a tank like yours, my personal preference would have been plywood, and Silicone I would have been more than sufficient.
Backfromthedead
wednesday13
are the go-to guys for larger all-glass and/or acrylic tanks.
The thing is...it's all BS. There are any number of silicone sealants that are marketed as being 100% pure silicone, but which contain anti-mildew agents and who-knows-what-else, so by definition they are not pure.
I've gone through numerous case lots of Silicone I over the years, both for building all-glass tanks (mostly smaller tanks, 50 gallons and under) as well as for sealing and adhering glass panes into larger plywood tanks. I also run a bead of it around all inside seams of plywood tanks as insurance, and use it for all kinds of smaller aquarium jobs as well.
I understand that there are other silicones available that produce stronger bonds, and which would likely be preferable for actually building larger tanks, but I've never looked into them personally because I don't need that kind of performance, and I try to avoid fixing things that ain't broke.
If I had built a tank like yours, my personal preference would have been plywood, and Silicone I would have been more than sufficient.
Backfromthedead
wednesday13
are the go-to guys for larger all-glass and/or acrylic tanks.
Sorry to hear about your dilemma, sounds like a real pain. First thing to do is identify what actually caused the failure for sure. Its unlikely that a tank that had operated for a long time previously would suddenly fail in the manner you described just from the seals being worn out. Usually an old failing seal will just barely leak at first as the water finds its way through small voids in the structural seam.
Can you think of any impacts/drops/otherwise trauma the tank mightve been through in transit from the sellers to your place? This would be an easy explanation.
The fact the seller even mentioned the reseal would be funny to me, possibly a hint that something had been awry with the tank previously. If i was to bet, i'd say the tank had developed a leak for some reason, the owner tried to do a patch job over the spot which may have held for a very short time before failing.
Post some pictures of the tank. If its the marineland 72x36x27 tank, i know youre not alone, ive read probably a dozen accounts of the tanks failing catastrophically for different reasons. If the support frame is worn out or damaged you may have to tweak the tanks design before rebuilding.
As for the silicone, a lot of builders swear by momentive rtv 108 for larger glass tanks like this. It is supposedly the ideal mix of workability and strength and available in black or clear. Ive personally worked with dow corning 795 black and GE SCS1200 clear on larger tanks DC 795 is neutral cure (less stinky) and easier to work with imo, cures slower. SCS1200 is acetyl cure (stinky) and cures very quickly, but once its set theres nothing stronger to connect glass with imo.
Next time i build a larger tank i plan to try out rtv108 and see how it fares. Theres nothing wrong with ge silicone 1 and i cant say its a bad idea. Its plenty strong enough to do the job but its generally advised to use a structural adhesive like the ones listed above when youre dealing with tanks as large as yours.
Can you think of any impacts/drops/otherwise trauma the tank mightve been through in transit from the sellers to your place? This would be an easy explanation.
The fact the seller even mentioned the reseal would be funny to me, possibly a hint that something had been awry with the tank previously. If i was to bet, i'd say the tank had developed a leak for some reason, the owner tried to do a patch job over the spot which may have held for a very short time before failing.
Post some pictures of the tank. If its the marineland 72x36x27 tank, i know youre not alone, ive read probably a dozen accounts of the tanks failing catastrophically for different reasons. If the support frame is worn out or damaged you may have to tweak the tanks design before rebuilding.
As for the silicone, a lot of builders swear by momentive rtv 108 for larger glass tanks like this. It is supposedly the ideal mix of workability and strength and available in black or clear. Ive personally worked with dow corning 795 black and GE SCS1200 clear on larger tanks DC 795 is neutral cure (less stinky) and easier to work with imo, cures slower. SCS1200 is acetyl cure (stinky) and cures very quickly, but once its set theres nothing stronger to connect glass with imo.
Next time i build a larger tank i plan to try out rtv108 and see how it fares. Theres nothing wrong with ge silicone 1 and i cant say its a bad idea. Its plenty strong enough to do the job but its generally advised to use a structural adhesive like the ones listed above when youre dealing with tanks as large as yours.
Yeah, that raised my eyebrows as well...but then I'm not very trusting...
Honestly, calling this project a "re-seal" is kinda sorta inaccurate, IMHO. A re-seal, to me, means that you remove the entire internal bead from the tank, but carefully leave the tank fully assembled by not touching the silicone that is actually between the panes and holding them together. The interior bead is a bit of leak insurance and a bit of a cosmetic finisher; it doesn't hold your tank together. You can build a tank quite effectively by taping off the glass right up to the adjacent piece, applying the initial bead to all surfaces, assemble the structure and then peel off the tape, leaving no bead visible inside the tank at all. It's more work, more time-consuming and doesn't look "right" to the eye accustomed to that bead being there.
But you're way past that point. You need to tear down the whole dang thing and re-build, not just re-seal.
The gent for whom I worked back when I was in school, and who had built countless tanks over the years, never applied the interior bead separately. His application of the initial structural bead was so precise (and fast...), and his skill in assembling the glass panes so artful, that he would slap the glass together and there would be just enough silicone squeezed out on the inside that a finger could be run over it immediately and produce that lovely, even, straight corner bead that we all want to see. On the rare occasions that the bead required a slight extra dab here or there, or a bit of cleaning up...he was embarrassed.
I can't believe those Marineland DD 300g tanks are still being made. Those tanks have been splitting on the bottom for over 15 years now and nothing seems to change with them.
Marineland should be ashamed.
Lol, yeah. I wouldnt be surprised if all or most of the failures came from one bad batch or time though. Couldve been something theyve fixed over time. Ive actually seen several of these tanks in operation doing just fine over the years though.
I had called Marineland recently, as I wanted to see if they still produced the 7 foot 265. They said they discontinued that, along with the 300 dd. Just an fyi.
I wouldn't replace this tank with another Marineland. no way. Go Aqueon. My 150g has been up and running for 15 years no issues and the glass on this tank is thicker than any on the Marineland tanks, its one of the reasons I went with Aqueon when I was researching which tank to buy back in the day.
Granted, you can only get the 210g but it will last and last and last. Peace of mind is priceless IMO. my 90g is also aqueon and its 10 years old now as well.
For big tanks, go Aqueon.
Granted, you can only get the 210g but it will last and last and last. Peace of mind is priceless IMO. my 90g is also aqueon and its 10 years old now as well.
For big tanks, go Aqueon.
