Removed my sandbed

[Anonymous]

has anyone had any success getting anything at all to stick to starboard?

We never had any success with it on boats as far as painting or epoxying or anything.

They do offer different colors though

 

[Anonymous]

I don't think anyone has had much luck with stuff sticking to Starboard.

I think the trend is away from Starboard - it originated with one person. Now that more people are looking at BB more ideas are coming.

 

[Anonymous]

http://pnwmas.com/modules.php?name=Foru ... opic&t=209

 

[Anonymous]

I was asking because I had a customer that insisted on trying to paint it. I called the company (starboard) and they said if you very coarsly sand it with a good coarse disc putting many many groves in it, and then paint it with a very good primer, and then some really high quality topcoat paint, it may in fact stay on for about 3 days, but they wouldn't guarantee it :lol:

 

[Anonymous]

Thanks Pod.

If I were going to cast a FSB on a board instead of just casting the epoxy, I would use egg crate because it is way cheaper than Starboard.

 

[liquid]

Slather PVC cement on the UHMW and scatter aragonite over it and press it in real good.

Shane

 

[polcat]

The bottom gets covered in coralline anyway....I had a glass bottom and it looked good, I also like the new starboard. It's really not the bottom that's important. The idea is to have huge flow (without a sand storm) so the skimmer can take out the suspended detritus. Seems we like to get wrapped up around the asthetics of the bottom when really that has little to do with this "method". Heck, put mirrors on the bottom... anything but sand

 

[Anonymous]

Why not just mix the epoxy and sand and dump it right in the tank - being careful not to leave any on the glass?

 

[Anonymous]

Why not just mix the epoxy and sand and dump it right in the tank - being careful not to leave any on the glass?

That would be a very good way to destroy the glass tank bottom.

 

[liquid]

That would be a very good way to destroy the glass tank bottom.

Huh? As long as the epoxy polymerization exotherm didn't get too hot it shouldn't be an issue. Or are you referring to something else? The only problem you'd have would be that you'd never get the stuff off the bottom of the tank.

Shane

 

[Anonymous]

Or are you referring to something else?

I've seen glass crack from adding water to tanks with epoxy faux-bottoms cast in tank.

The only problem you'd have would be that you'd never get the stuff off the bottom of the tank.

Which also sucks.

 

[Anonymous]

Or are you referring to something else?

I've seen glass crack from adding water to tanks with epoxy faux-bottoms cast in tank.

The only problem you'd have would be that you'd never get the stuff off the bottom of the tank.

Which also sucks.

I can actually understand that

If the epoxy and sand is added at the same time any sand that is on the bottom will be a pin point of pressure on the bottom.

How about if you add a thin layer of epoxy to the bottom, let it dry, and then add a second layer with the sand in it?

It would be impossible to remove which would suck, I agree

 

[Anonymous]

Why would you need to remove it?

Self leveling epoxy always has a smooth botton IME and does not expand enough to push out the sides of it's container. The SC aquarium has tanks made this way.

 

[liquid]

If the epoxy and sand is added at the same time any sand that is on the bottom will be a pin point of pressure on the bottom.

And where would the pressure come from?

Galleon and I discussed this on IRC while the server was down last night. What we think is happening is that there is a shrinkage differential between the epoxy and glass that causes a higher stress plane on one side of the glass compared to the other side. If the epoxy layer is thick enough, the resulting stress differential causes catastrophic failure. His description of what the shards of glass look like ('serpentine' IIRC), lead me to believe it's a stress differential related phenomenon. It could be a temperature related stress phenomenon or possibly even a water absorption differential phenomenon or even a polymerization shrinkage phenomenon. I doubt it's water absorption as epoxies by design are very chemically inert and will not soak up appreciable amounts of water. The other two are plausible IMO. I've seen this stress failure phenomenon like this in other polymer systems I've worked with in my 11 yrs as a coatings chemist.

Shane

 

[Anonymous]

Shane, that may well be true, but I can't imagine epoxy shrinking or expanding enough to pose this problem. The epoxies we use for food prep work and in hospitial/OR are very stable and do not shrink. Or am I just not understanding your post?
Andy

 

[Mighty Quinn]

Hello Everyone,

Sorry for my delay on getting back to you guys. Work is getting pretty busy so I haven't had much opportunity to pursue this topic.

As promised, I posted a request on Dr. Ron's forum over on RC. You can read his response at:

http://reefcentral.com/forums/showthrea ... did=548275

Ron provided numerous references and some explaination for why DSB's are different from the sediments that most publications are based on. I have to admit that I have not had time to get to the library and read these references yet.

Well, this should stir the pot a bit. :wink:

Kindest regards,
Quinn

 

[DK]

Hello,

"Even then you are guessing as to how much p remover to run and at what rate and when to change it. Then you are guessing "

I reccommend that you test for P once a week. This yields very little guesswork and since this process goes slowly, I just can't agree.

Again, the powerhead in the sand is a mostly bacteria issue, not a phosphate issue. When securing a power head, I place the powerhead and secure it and as a backup, I secure the cord so if it dislodges, it doesn't have far to go. Yes, if it points straight down, it will disturb some of the bed but IME , I have had little or few losses this way. A tunze is a different story but is easier to secure using ties.


I have seen many corals (especially LPS) right on the sand. Also sand will collect in pockets on the reef from storms and animal action so sand is actually quite close.

I have never recharged my sand beds so the "life" in my beds is not as visible - but so what. At night it is covered with pods and mysis and even a few bristle worms show up. If the denitrification is occuring in the upper portion of the bed, I really don't care then. In my SPS tank, I have high flow which is enough to keep it relatively clean. In my other tank, I will get growth on the bed and I will siphon it off every couple of months if it mats but again, so what.

I will be setting up a 220 in the near future and will have to address this issue for that tank soon I guess that if I try the faux sandbed and hated it, I could add sand on top of it hummmmmm.

 

[liquid]

The epoxies we use for food prep work and in hospitial/OR are very stable and do not shrink.

Any polymerization reaction will cause a net change in density (i.e. shrinkage) -- some more than others. Some epoxies are specially formulated to be low to zero shrinkage and you're going to pay a higher cost for them. Some aren't. Not all epoxies are the same. The epoxies that I work with (which are UV cured) can have net shrinkage rates of upwards of 10%. Granted this is an extreme for coatings. The standard catalyzed epoxies -- even if they shrink only 1% (which isn't much) -- can cause large planar forces on a surface given enough distance. For example: if an epoxy formulation shrinks only 1% upon cure, on a 6' tank bottom that will cause a net shrinkage of almost 3/4" down the length of a tank bottom. That's a fairly large stress IMO.

Shane

 

[Anonymous]

Hello,

"Even then you are guessing as to how much p remover to run and at what rate and when to change it. Then you are guessing "

I reccommend that you test for P once a week. This yields very little guesswork and since this process goes slowly, I just can't agree.

The tests we have for p are inadequate. Even the ROWA guys agree and are supposed to be developing a better test.

Again, the powerhead in the sand is a mostly bacteria issue, not a phosphate issue.

Maybe!

When securing a power head, I place the powerhead and secure it and as a backup, I secure the cord so if it dislodges, it doesn't have far to go. Yes, if it points straight down, it will disturb some of the bed but IME , I have had little or few losses this way. A tunze is a different story but is easier to secure using ties.

I have had massive losses that way. At least 1000 dollars worth. Simply not worth the risk, IMO.

I have seen many corals (especially LPS) right on the sand.

There are corals that grow on the sand. These should prolly have sand in the aquarium.

Also sand will collect in pockets on the reef from storms and animal action so sand is actually quite close.

I think that is apples and oranges because it is not a permanent sand bed.

I will be setting up a 220 in the near future and will have to address this issue for that tank soon I guess that if I try the faux sandbed and hated it, I could add sand on top of it hummmmmm.

 

[Anonymous]

Shane, that may well be true, but I can't imagine epoxy shrinking or expanding enough to pose this problem. The epoxies we use for food prep work and in hospitial/OR are very stable and do not shrink. Or am I just not understanding your post?
Andy

The one that I saw that cracked seems to have done so due to a rapid temp change in the glass. Don't know if it was tempered or not.

What do you guys think about epoxy on the silicone joints?

I would want the FSB removable because a big glass tank is already too heavy!