Breeder evaporating blocks

I am using a breeder from the good reactor design thread:

Breeder 1:

• Link: http://www.talonfiremage.pwp.blueyonder.…114010101001019
• Heating configuration (with timing): Run this for 5082 secs http://www.talonfiremage.pwp.blueyonder.…114010101001010
• Breeder efficiency: 8
• Efficiency: 1
• Eu/tick: 10
• Lava buckets: 194
• Cost: Iron 160, Copper 196 and Tin 105
• Credits: Rick

I am using falling water from far enough above it that those source blocks do not evaporate... however the water blocks under the chambers (where the falling water is blocked) do evaporate. Once that happens this design goes positive for me (with the neutral setup). It is only very slightly positive but I have have to keep an eye on it and I put 10-15 water buckets in it every 30 mins or so to knock it back down to 9000. Is there a way to avoid this? Or should I not worry about it? I'm not sure what temp it will reach if I don't ever put any buckets in by the time the uranium cell runs out. If I go over 10k I am assuming I start to lose reactor components and it would snowball quickly from there so I haven't let it get close to 10k at all.

What is the trick? I got the top covered with source blocks which is what I have seen in videos but the water does not go into the square under the chambers. And if I put additional source blocks in there or anywhere near the reactor they get evaporated.

I can't really tell from that picture but is the bottom chamber sitting in the ground? Mine is off the ground by a square. Maybe that is the problem. I figured I needed to have it off the ground for the cooling.

Are the cooling blocks 3x3 centered on the reactor or 3x3 centered on each chamber in the reactor? I.E. if you have a 6 chamber reactor does it get any cooling from having water on the sides and top and bottom of the chambers (those squares would be outside the 3x3 centered on reactor itself).

Yea that seemed to do it... filled in the bottom with blocks rather than leaving a space for water and it is cooling much better now. Thanks.