I see, so you're saying that the bottom of the tank does not sit completely flat on the plywood and you see gaps between the tank and plywood? Either the tank is not flat and/or the plywood is not. I'd be curious if it would self correct once you fill with water (without other risks of course)?
Question about styrofoam under acrylic tank.
- Thread starter Tanganikajunkie
- Start date
-
- Tags
- fresh water sump
Do you know who made the tank? A call to them is the single best advice you can get! It happens a lot with the salt forums, but people ask what type of foam or how to support various style of tanks. Always try and find out the manufacturer and listen to what they say.
o.p. yes its common for a tank/stand to not be level.... u can use an additional piece of ply like u did with the foam... then use shims to eliminate any "air gaps" by placing the shims in between the ply and the top of ur stand. u can also place shims right under the acrylic in the gaps u see... under the ply is the better way tho. no biggie 
... this is typical. some mfg glue a piece of ply directly to the bottom of their acrylic tanks... this is y
... this is typical. some mfg glue a piece of ply directly to the bottom of their acrylic tanks... this is y
mfg's dont matter... foam is not for acrylic tanks...end of story, no matter how many people think its right. Ive personally done it and seen the effects/failure over time. Ive also helped alot of members repair their acrylic tanks that failed on the bottom seams after being placed on foam... Shimming a tank and stand of any model/make/type is common practice. It may be a hassle to get it perfect but it pays off down the road.
Well then the manufacturer should say to not do that - no matter how many people think it's right!
It can be hard to tell who really knows their stuff on the Internet and how many are time bombs, which is why I like talking with manufactures. Clearly many MFK members know their stuff and no disrespect intended, just normally like to hear straight from who made it in case there is something unique that might not be clear at 1st.
I understand you don't know who made it, but it's surprising how often this question comes up on forums with glass rimless tank too.
It can be hard to tell who really knows their stuff on the Internet and how many are time bombs, which is why I like talking with manufactures. Clearly many MFK members know their stuff and no disrespect intended, just normally like to hear straight from who made it in case there is something unique that might not be clear at 1st.
I understand you don't know who made it, but it's surprising how often this question comes up on forums with glass rimless tank too.
How did I know I'd see you in this thread haha?
I always meant to ask you... so you have said in this thread and others that it can/will lead to bottom seam failure. So do you contend that if you put the same two tanks to the test, one on plywood and one on foam and plywood, the one with the foam will fail quicker 100% of the time? Massive loaded question I know, but I am wondering if it's one of those "you probably shouldn't do it but plenty of people are fine with it" or "I'd get that foam out of there asap" situations. Just wanna know if it's something to live by like making sure a tank is level or more of a common opinion.
Edit: and I see you answered most of my question in a subsequent post, should learn to read threads as a whole before replying lol.
personally, "id get that foam outta there asap" to answer ur ? lol.... so many people use it now under acrylics that not many people believe me.... until they have issues... then i get contacted with repair ?'s. been there done that myself just the same so i understand the discrepencies on this topic and have seen the resuls in person. Foam will not level ur tank, it may decieve you into thinking so but it comes down to the same principle of leveling a tank properly. leaning one way or the other will surely make the "bad side" recieve more pressure, leading to issues over time. as u say urself leveling a tank is known to be a major issue. this is the same topic imo. foam can crush/distort over time making air gaps u tried 2 eliminate in the first place or make the tank unlevel. alot easier to not use it from the start and level the tank properly out of the gate. May sound like a stupid refrence, but watch an episode of "tanked"... they glue a piece of 3/4" ply to the bottom of every acrylic tank they sell/set up. theyve been in the buisness long enough 2 have seen the results of a non leveled tank, im sure they didnt do this from the start. makes for easy shimming tho inbetween the ply and stand. Honestly its better to not use foam and fill in air gaps directly under the acrylic with shims, then to use foam and think uve solved the problem.
Another reason y it may seam right to use foam is alot of guys dont keep there big tanks for long... they may be set up for 1-2 yrs and run fine with foam for that said time until there moved and resetup, but leave one there for 10yrs next to one without foam and yes i guarentee there will be visual discrepencies in the seams of the tank on foam just as there would be doing the same test of a tank that is leveled properly next to one leaning to one side.
Everyone wants to set up there tanks asap... foam is a cop out to make an acrylic tank level. its not always easy to level large tanks so i understand. doesnt make it right tho. Getting a 4x8 or said piece of foam home and under the tank without crushing it in some spots is almost impossible, let alone placing a tank on it with a few guys. soon as its crushed/distorted u start losing support in those areas and over time that problem grows. im sure i sound like a broken record by now, just trying to help others with problems ive experienced myself.
I hear you man. In my case it is simply a case of the last owner that had it used it, and when I bought it as my first monster tank I just followed what he did. It still sits under my 400, either 3/4" or 1/2", I think 1/2", the pink stuff. I mean I am not going to drain my full tank, empty a chunk of the gravel, and risk screwing up the PVC piping just specifically to take it out, but best believe next time the tank gets drained I will surely not use it again. Hopefully I am one of the lucky ones and it won't lead to catastrophe being up for a couple more years before I do that.
wednesday13 is spot on with his advice - foam is only for glass tanks with no rims.... period. Most manufacturers will tell you the same, and most will void their limited warranty if you decide that you know better. Good luck with your new set up.
