I need to replace the circulation pump on my hot tub. The model number of the pump is SM-909-NHW-18. While browsing for a replacement, it seems that the barb can be either 3/4" or 1". Unfortunately, it doesn't say what size mine is anywhere on the old pump. I'm fairly sure that it is 3/4", but it would suck to order it and find out that I needed 1" instead. The spa is a Sundance Capri made in 1998. I don't think the circulation pump is the original. How safe do you think it would be for me to order the 3/4" barb? Thanks for any input.