Condensation Issue

If the double glass panes are sealed and have dessicant strip inside there should be no problem, the proximity of the swimingpool/waterfall or anything else is irrelevant.
If they are not sealed, then you will doubtless have a problem, forced air, may keep down the condensation, but it will probably end up as a dirt trap.
Del

..I would start by blowing in some air.... stale air..

my turtle tank has about the same dimensions and issues.. When I blow some air into it.. the foggy drippy glass clearly dries up..

Whenever there is a difference of temperature and pressure of water vapor across a structure, conditions may develop that lead to a condensation of moisture. In addition to the structural modification on the doors/windows operation and maintenance of a.c system is also important to minimize the condensation problem on the glasses of the windows. To minimize the condensation on the glasses of the window please instruct the operating team of ac system to maintain a room dew point lower than the lowest expected surface temperature in the room .If need velocity of air can be increased to decrease the surface resistance to bring the surface temperature of the window closer to the room dry- bulb temperature

Because OP states that he has the option of supplying the gap with fresh air, one can be assume that the gap between the two plates is not sealed. In that case, I recommend you seal the gap and proceed as in answer #1, or feed warm dry air between the gap from the bottom. This will act as a defroster. Your objective will be to keep the internal surface temperature of both pieces of glass above the dew point of the adjacent gas.

A water fall 60cm from the glass and your worried about condensation. I would think that you would have continuous spray from the falls on the glass. This will leave behind deposits that will continuously need to be cleaned off. Even if the double panes are sealed you may have a problem. What is the seal material? The butyl rubber that the normally use as sealant for house windows does not hold up well to continuous moisture. If the seal fails you will have these deposits between the glass.

You might try air curtains to keep spray to minimum on the falls side. On the inside the air curtain movement of air should keep condensation from happening

Thanks for all the replies,

OZZB, as i understand from your answer that if there is no spray of water to the glass, then there is no possibility of condensation. The glass to be used is a laminated type.

The area of concern is the one between the glass and the water fall not that between the layers of glass

Thanks again for all of you

In that it's 'spray', not condensation. Try RainX or some similar water repelling product.

Adding a 'wetting agent' in the fountain water is also an option. This will cause the droplets to join and flow off as a film - which you can see through.

No My comment was that with a water fall that close to the glass, spray would be a bigger issue then condensation.

First what is the temperature difference between the two spaces? Both you have said are air conditioned? The lamination in the glass is an additional thermal barrier though it is I believe being used as sound suppression. The glass is it double pane sealed Insulated glass unit? Is it Argon filled? What is the dead space between the glass? What is the spacer material that keeps the two panes of glass separated? Spacer material is the biggest cause of thermal conduction across the glass. Aluminum has high level of thermal conduction. What is the frame material the glass is to be put in? As it also can cause conduction from the inner space to the outer.

All that being question has bearing on whether it will condense water.

Now an air curtain placed to force air down the face of the glass should stop any condensation to form on it. Will also reduce the amount of spray that would come off the water falls and land on it. Air motion across the surface of the glass will increase evaporation of any water no matter how it formed. Helping to keep it dry.

If money is not an issue, then I would suggest you replace the air space with nitrogen, after drying it out well and the sealing the double glass sections.

If money is an issue then maybe recirculate dry warm air through the ar space between the glasses.

The glasses will always receive droplets from water fall. Condensation will be avoided if supply of chilled air is directed away from glass & towards room space; also keep return air path away from glass if possible atleast by 30cms