Humidity, Evaporation, Jumping fish , Dirty/salty reflectors SOLUTION!!

[roland jacques]

Humidity, Evaporation, Jumping fish , Dirty/salty reflectors. SOLUTION!!

GLASS TOPS!!!!????

It seems that we goting away from glass tops. Why?

Id like to here your PROS and CONS.

After 1 short test i found light loss through some old calcium stained glass tops, only noticing about a 10% lose in light (lux meter only test) i would appreciate anybodies else's test results in this area.

1. Some say we lose to much light. but you can put your lights closer and your reflectors don't get dirty. so do you lose light or gain?

Sammy noted that he looses 90 PAR (looks like 20%) when his T5 bulbs & reflectors get dirty (every few weeks) from salt splash. Cleaning them is a real pain. It seems to me that cleaning a glass top is much easier. (assuming your lights are mounted above the glass.

2. You lose surface gas exchange.
How much Gas exchange can actually take place? how much do you want? if you have a sump with agood skimmer or... i would think that could be enough to achieve air water equilibrium in your tank. PS You can make the glass top NOT seal off the tank buy making a spacer for them...


I'm thinking of making single pane glass tops for my holding system (framed in plexi for easier handling and maybe a thiner glass) Ill probably make 2 sets so i can just swap them in and out of a trash can filled with a cleaning solution.
What kind of glass to use the thin stuff at HD, Lowes... or some type of solar glass? I'm not sure what would be best.

I want to no what you guys think about glass tops

 

[cameron]

1. Depends on the glass honestly.

2. Skimmer gas exchange is HIGHLY overrated. Most gas exchange happens at the surface and theory goes you need a lot of it. Supressing that exchange can easily lead to depressed pH. How much do you need? I have no idea, but I certainly don't want to rely on one return pump to keep my gas exchange going in the tank.

3. Heat. Most of our tanks evap to keep the tank cool but sealing off the tank you liimit the cooling.

That said, you bring up some interesting points. Perhaps opening up a small section near the back of the tank would be plenty for gas exchange to occur and bleed off some of that heat. I may consider that idea since my lights are right on top of my tank anyway.

 

[calireefer]

I like the look of an open top tank enough that I'm willing to put up with the cons.

 

[roland jacques]

Yeah the glass i briefly tested was Factory AGA top about 3 years old and i was surprised to only see a 10% drop in LUX. If i used a better glass...

I see a lot of LPS and Soft coral tanks with glass tops on them. I cant really concluded much from that. Other than to say they do get enough gas exchange for the corals to live and grow with good pH.

Heat, yeah i can see it holding in. but at the same time in a well vented canopy it may prevent some heat from getting in from the lights.

Somebody sent me a video (that i cant see right now, have to wait for my son to fix the comp video player, so i don't no what it about) he says this video goes into why gas exchange at the surface is not that important.
click on oxygenation video http://reefvideos.com/">http://reefvideos.com/</a>



(I can't agree on the skimmer/ sump gas exchange because not all skimmers and sumps are created equally. Even overflow boxes create a bit of gas exchange. I'd say an ATI type skimmer would give maybe 50 Xs more gas exchange than a small ASM type skimmer. NOT THAT ASM ARE BAD!!)

 

[jefft]

I like the idea also, I'm constantly cleaning my bulbs and reflectors. I think I would get enough evaporation for cooling in the sump and that is where my cooling fan is anyway. The back 2" has to be open anyway because of wires and HOB overflow so a little exchang/cooling could happen there. Thanks for mentioning it I also will try it. Jeff

 

[glxtrix]

I'm too much of a stickler to loose any PAR from the glass. I'll deal with it as it comes.

 

[roland jacques]

calireefer;128380 wrote: I like the look of an open top tank enough that I'm willing to put up with the cons.

I like the look of a MH hanging over a open top tank also.

 

[roland jacques]

glxtrix;128397 wrote: I'm too much of a stickler to loose any PAR from the glass. I'll deal with it as it comes.

But are you really loosing PAR?
Your Lamps closer, and your refectors cleaner, and some type of glass to go through?
I think you may actually gain PAR.

 

[glxtrix]

nah, you're def going to loose PAR going thu glass. Not to mention having to take them off every time you need to do something to your tank. Water splashing on them, salt creep, salt etching....too much for me to worry about. But hey if it works for you, duit up

 

[kwl1763]

And you have to incesently clean them. The heat and gas exchange are by far the biggest issues but ask anyone with center braces what a pain they are. Would be the same with glass tops.

 

[roland jacques]

glxtrix;128408 wrote: nah, you're def going to loose PAR going thu glass. Not to mention having to take them off every time you need to do something to your tank. Water splashing on them, salt creep, salt etching....too much for me to worry about. But hey if it works for you, duit up

Im talking about PAR in the tank.
Everyone knows you loose PAR going through glass. I mentioned that already. The question is how much? I think it is worth more testing. I tested badly etched, old, kind of thick regular plate glass, and only lost 10%

If the PAR loss is less than 10%, through the glass.
but you gain 20% buy having cleaner reflectors
and then you can mount your T-5 lights 2" closer gaining another 40% PAR
-10 +20+40= I dont see how you can say you will deff loose PAR (in the tank)

The PAR in your tank could be higher.

 

[lorenk]

It was an ever constant battle to keep my glass lids clean. The water that tried to evaporate just left white film on my glass.

I don't find myself with dirty reflectors personally.

 

[cameron]

Roland Jacques;128384 wrote: Somebody sent me a video (that i cant see right now, have to wait for my son to fix the comp video player, so i don't no what it about) he says this video goes into why gas exchange at the surface is not that important. click on oxygenation video

I couldn't find any reference in his real world examples of his covered tank. He did sealed and sterile with nothing in it, but that isn't a test just a control.

Roland Jacques;128384 wrote: (I can't agree on the skimmer/ sump gas exchange because not all skimmers and sumps are created equally. Even overflow boxes create a bit of gas exchange. I'd say an ATI type skimmer would give maybe 50 Xs more gas exchange than a small ASM type skimmer. NOT THAT ASM ARE BAD!!)

Skimmers contribute very little to total Dissolved Oxygen for the total tank even his above presentation bears that out. Skimmers hit the 100% mark in only a small amount of the total tank water. Flow and lighting are far more important. How much flow effects oxygen with a covered tank I couldn't garner from his presentation, but I would guess it diminishes as their is less oxygen in the sealed top. If flow on a sealed tank is enough, you are good. If it isn't, things are going to croak and/or pH is going to drop like a rock.

The sump likely is the place where you will get this idea to work without any loss in oxygen or pH, but if the return fails it would be interesting to see if the pumps in a sealed tank can keep it going.

As for heat in the winter no big deal. In the summer, I would strongly advise a fan over the sump.

 

[cameron]

Another idea is to simply lower the water level in the tank so you get more space between the cover and the water which would greatly reduce splash on the glass. Works with bulbs and reflectors too.

 

[roland jacques]

kwl1763;128423 wrote: And you have to incesently clean them. The heat and gas exchange are by far the biggest issues but ask anyone with center braces what a pain they are. Would be the same with glass tops.

When are you going to post some photos of your tank? i watched your build on RC looked awesome, but I never saw the finished tank.

I disagree on the cleaning part.
Ive found that if the glass tops that do not get hot clean fairly easily. And a cool glass top can go a month without needing cleaning.
As far as cleaning goes, is it easier to clean a 1 piece glass top, or 6 parabolic reflectors and Six T-5 bulbs every month?

I agree, heat could be an issue for some. But most Florescent tanks i see, they don't have a heat issues. (mine actually need more heat)

I'm still not sure about measuring the important of surface gas exchange. and exactly how much air contact you need to get equilibrium in a closed system. but there are ways to deal with that.

The one piece glass tops i made for the tanks at my first store had a hole drilled in them for feeding... They had no salt creep issues with the one piece tops but they were heavy glass.

(I'm bringing this option up for florescent lite tank not MH)

 

[kwl1763]

I never have to clean my reflectors, seriously I haven't cleaned mine in the whole year 18 month or so I've had my tank up and they are still spotless. They are far enough away from the tank they don't get splashed.

If your water level was low enough and you were using T5s with fans then I think it could work but agian keep them clean. You probably only lose 10-20% with clean glass but I'm sure you leave them on there a month and you're losing 30, 40, 50%?.

I've been looking for solutions to quit using eggcrate myself. I was thinking of making a 1/2" PVC frame and drilling holes and threading fish line through it.

You just have to keep up with the thread. i update it every couple months! Here is the latest FTS (actually from early Dec) and I linked the thread so you can keep up

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http://www.reefcentral.com/forums/showthread.php?s=&threadid=694606&perpage=25&pagenumber=1">http://www.reefcentral.com/forums/showthread.php?s=&threadid=694606&perpage=25&pagenumber=1</a>

I honestly think with an open sump and T5's this might work. Your sump if turned over a reasnable at least 5 times should provide enough gas exchange i would think!

 

[tonester_man]

I have a 90 gallon with a wet/dry filter, canopy without fans, and T5 lights with builtin fans.
As of right now:
I use All-Glass Versa-Tops and only have to clean them once every 2-3 weeks.....
(Like this one: http://www.petsolutions.com/All-Glass-Versa-Tops+I15929016.aspx">http://www.petsolutions.com/All-Glass-Versa-Tops+I15929016.aspx</a>)
I use the glass tops that have a hing on them so i can easly manage the tank (Used this style on my old 55 also with same results).
I do not add the plastic back strip to let the gas leave the tank. Not sure if it really helps though.....
My evap rate is about 1/4 to 1/2 gallon a day
Don't have an issue with jumping fish....

 

[roland jacques]

Your tank looks Great, thank for the link.
I will take my lux meter with me this week and test some more glass tops and see what decresses I see. I dont think ill see more than 15% decress but we will see.

dawgdude, a small air pump puting air under the glass tops will proved a good bit of air turn over in that tight of a space. it should give good gas exchange