Pond Boss Forums INTRO Questions & Observations Pond Liners for spawning beds?

Hi Bowie - welcome to the forum! You're the envy of many of us having Mike Otto work on your pond - congrats!

Using a liner to prevent spawning substrate [rock, gravel, sand] from sinking into the clay is a great idea, and one used by many on the forum - especially for beaches. The problem Randy identified I too have experienced and is that over time organic material/silt will eventually accumulate on top of the spawning substrate - liner and all. In my experience with my SMB beds the material eventually becomes too thick for fish to effectively fan it away and the beds become undesirable or are ineffective.

The accumulation of muck on my SMB beds served as impetus for the plan to develop raised spawning beds. Using materials I had on hand, I chose cinder blocks to elevate the beds from the pond bottom, then placed a wooden pallet on the blocks, laid a plastic or wire mesh on top of the pallet, then added my spawning substrate. The elevated and porous layers of material allow any particulate to fall through, while holding my substrate in place. Any material that does accumulate on the spawning beds is minimal and easily fanned away by the spawning fish so far. The first season I employed the elevated beds the SMB immediately used them, and abandoned the original beds I had in place. I was concerned they might not take to the elevated/engineered approach, but I surrounded the beds with limestone cobble to make them appear, at least to me, more natural.

Few issues when applying this to a panfish species. First, you're dealing with finer and lighter particulate for your beds while for SMB I'm using 3-6" limestone rock. For finer material, you'll need to reduce the size of your mesh to prevent it from passing through, while still allowing sediment/silt to pass through. While sand might not work, utilizing pea gravel or coarse road gravel might be the solution.

Also, the lighter substrate will more easily spread when being used for spawning and fanning year after year - so you'll need something to keep it in place. I use cinder blocks to create a horseshoe barrier around my rock, and you might be able to also. Additionally, I use baby wading pools for my BG/RES beds and it keeps the gravel in place, year after year.

Here are some photos of my SMB beds that might be helpful. Of course, BG will spawn on anything, anytime - so you might not need to design anything too special. Still, I would enjoy watching your progress should you decide to employ any of the ideas suggested by the forum.

This the condition of my SMB beds following two seasons of spawning - not good!



Here's the palleet elevated on blocks:



Mesh placed over the pallet upon which I'll place the spawning substrate:



Cinder block horseshoe and limestone bed implemented:





Here's the rock and PVS added to make it appear more "natural" and allow SMB fry some places to hide: