Hi Lisa - thank you for joining the site. I wanted to add that Behr had many friends in the community, and he will be sorely missed
I am sure that a fellow bonsai enthusiast who ends up with any of his trees will do his/her best to maintain them as a lasting memory to a great person. Bonsai is an interesting hobby because trees will greatly outlive any individual bonsai keeper. I develop my trees with the understanding that there will probably be a day when the trees go to someone else. If I do a good job, that other person may even want them
In the case of a bald cypress (before we see the photos) it is impossible to overwater them. They are one of the few trees that can grow with their roots completely submerged in water. It is more possible to UNDER water them than to overwater them. Let it sit in a bucket or pan of water and then you won't have to worry about it drying out in the hot Texas summer.
If the tree is stressed, especially if it might have suffered root shock recently, be very careful about fertilizer. Do not fertilize bonsai like a garden - because the trees are kept in small pots it is very easy to overfertilize and burn or kill the tree. Avoid chemical fertilizers entirely, and use organic if possible. If you want to use a product like Miracle Grow, always water your trees first, and then use Miracle Grow at half strength in solution. Bald Cypress likes acidic soil, so an acid fertilizer like Miracid would also work well (or else you can use an acidic soil mix with a lot of peat in it).
Here is some info from another site on Bald Cypress and Chlorosis:
Symptoms
Needles Turn Yellow - When Bald Cypress needles turn yellow in the middle of the growing season, the tree may be suffering from chlorosis. New growth at the ends of twigs is slowed and the tree develops a stunted appearance. Damage is more severe and obvious on new growth rather than established growth. There is a real possibility that entire branches will die, and eventually the whole tree might succumb if the condition is not corrected.
Probable Causes
Chlorosis - Usually chlorosis is caused by either lack of iron in the soil or its presence in a form that the tree can not take up into its system. Afflicted Bald Cypress may need slightly more acid soil to improve its access to iron, so add peat moss, sulfur or used coffee grounds to lower soil pH. Avoid using limestone or wood ashes that make soil more alkaline.