Question about styrofoam under acrylic tank.

spotfin

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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.
What would the visual discrepancies look like? I think I'm going on 10 years of sitting on foam. My tank was purchased new and hasn't moved since.
 

Tanganikajunkie

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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.
Ok so say there is a gap between the acrylic and the plywood how would I fix it I hear ur points and it makes sence but I need to get this done I have fish coming on Saturday and need to get it running. I have plenty of seeded media for my filter so I'm not worried about cycling. I know it stressful on the fish for a mini cycle but it's the way I've always done it.
 

wednesday13

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Ok so say there is a gap between the acrylic and the plywood how would I fix it I hear ur points and it makes sence but I need to get this done I have fish coming on Saturday and need to get it running. I have plenty of seeded media for my filter so I'm not worried about cycling. I know it stressful on the fish for a mini cycle but it's the way I've always done it.
stick as many shims as u can under those air gaps in between the acrylic and stand top and ur good to go. i like using the composite shims but reg wood shims will work just the same. the point of this is to support the seam of the tank... air gap here or there under the middle of the tank is not a big issue. supporting the seam of material is what counts.
 
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Tanganikajunkie

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stick as many shims as u can under those air gaps in between the acrylic and stand top and ur good to go. i like using the composite shims but reg wood shims will work just the same. the point of this is to support the seam of the tank... air gap here or there under the middle of the tank is not a big issue. supporting the seam of material is what counts.
Cool so I took the foam out and looked at the tank it looks pretty good I'm filling it up in the morning so we will see if it holds water fingers crossed
 

wednesday13

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Cool so I took the foam out and looked at the tank it looks pretty good I'm filling it up in the morning so we will see if it holds water fingers crossed
it wont cause a problem immediatly....i still advise the use of shims anywhere u can fit one... cple paks of shims might cost u $10 at the most. def. worth it for the longevity of the tank. good to hear its sitting pretty flush tho without the foam.
 

wednesday13

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What would the visual discrepancies look like? I think I'm going on 10 years of sitting on foam. My tank was purchased new and hasn't moved since.
Since ur tank is new i wouldnt worry much. Everything i buy is used and around 15-30yrs old so i see the effects of water pressure on acrylic and time a bit more than others. id take it out, but thats just me. Some things/signs to look for are any white patches on/inside the seam of material along the bottom permitter of the tank. Tank i had issues on using foam sunk forward a bit over 5 yrs and started seperating at the front bottom corners on both sides. Cant be a coincidence since it happened on each end and at different times. I finally removed the foam the third time it happened, repaird it again and shes been holdin out for me. Id guess u did a good job of leveling ur tank from the start, it was probably built well being made within the last 10 yrs also. i guess my biggest point on this subject is foam is not a cure all for leveling a tank properly and in my experience it can/will make the level/pitch worse over time. It can be comprimised easliy also during reg tank matinence also so y use it at all?
 

Lepisosteus

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agree with Wednesday no foam. For just an interesting test get a black of foam, place a piece plywood over top and then stand on the piece of plywood so your feet are near the edges, you will feel the strain on your feet and ankles
 
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Tanganikajunkie

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Since ur tank is new i wouldnt worry much. Everything i buy is used and around 15-30yrs old so i see the effects of water pressure on acrylic and time a bit more than others. id take it out, but thats just me. Some things/signs to look for are any white patches on/inside the seam of material along the bottom permitter of the tank. Tank i had issues on using foam sunk forward a bit over 5 yrs and started seperating at the front bottom corners on both sides. Cant be a coincidence since it happened on each end and at different times. I finally removed the foam the third time it happened, repaird it again and shes been holdin out for me. Id guess u did a good job of leveling ur tank from the start, it was probably built well being made within the last 10 yrs also. i guess my biggest point on this subject is foam is not a cure all for leveling a tank properly and in my experience it can/will make the level/pitch worse over time. It can be comprimised easliy also during reg tank matinence also so y use it at all?
Tank is used idk how old it is but it Seams pretty level I need to shim like two spots but over all I'm happy I didn't put the foam in
 

spotfin

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Since ur tank is new i wouldnt worry much. Everything i buy is used and around 15-30yrs old so i see the effects of water pressure on acrylic and time a bit more than others. id take it out, but thats just me. Some things/signs to look for are any white patches on/inside the seam of material along the bottom permitter of the tank. Tank i had issues on using foam sunk forward a bit over 5 yrs and started seperating at the front bottom corners on both sides. Cant be a coincidence since it happened on each end and at different times. I finally removed the foam the third time it happened, repaird it again and shes been holdin out for me. Id guess u did a good job of leveling ur tank from the start, it was probably built well being made within the last 10 yrs also. i guess my biggest point on this subject is foam is not a cure all for leveling a tank properly and in my experience it can/will make the level/pitch worse over time. It can be comprimised easliy also during reg tank matinence also so y use it at all?
Yes, I made sure it was level before I filled it. The foam is hidden on the front and sides by wood trim which is glued down, so I won't get a good look at it. I will be easier to see the back though.
 

spotfin

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agree with Wednesday no foam. For just an interesting test get a black of foam, place a piece plywood over top and then stand on the piece of plywood so your feet are near the edges, you will feel the strain on your feet and ankles
But isn't the weight of a tank equally distributed over the entire area of the foam, assuming it is perfectly level?
 
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